1.
Geographic coordinate system
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A geographic coordinate system is a coordinate system used in geography that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are chosen such that one of the numbers represents a vertical position. A common choice of coordinates is latitude, longitude and elevation, to specify a location on a two-dimensional map requires a map projection. The invention of a coordinate system is generally credited to Eratosthenes of Cyrene. Ptolemy credited him with the adoption of longitude and latitude. Ptolemys 2nd-century Geography used the prime meridian but measured latitude from the equator instead. Mathematical cartography resumed in Europe following Maximus Planudes recovery of Ptolemys text a little before 1300, in 1884, the United States hosted the International Meridian Conference, attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich, the Dominican Republic voted against the motion, while France and Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911, the latitude of a point on Earths surface is the angle between the equatorial plane and the straight line that passes through that point and through the center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels, as they are parallel to the equator, the north pole is 90° N, the south pole is 90° S. The 0° parallel of latitude is designated the equator, the plane of all geographic coordinate systems. The equator divides the globe into Northern and Southern Hemispheres, the longitude of a point on Earths surface is the angle east or west of a reference meridian to another meridian that passes through that point. All meridians are halves of great ellipses, which converge at the north and south poles, the prime meridian determines the proper Eastern and Western Hemispheres, although maps often divide these hemispheres further west in order to keep the Old World on a single side. The antipodal meridian of Greenwich is both 180°W and 180°E, the combination of these two components specifies the position of any location on the surface of Earth, without consideration of altitude or depth. The grid formed by lines of latitude and longitude is known as a graticule, the origin/zero point of this system is located in the Gulf of Guinea about 625 km south of Tema, Ghana. To completely specify a location of a feature on, in, or above Earth. Earth is not a sphere, but a shape approximating a biaxial ellipsoid. It is nearly spherical, but has an equatorial bulge making the radius at the equator about 0. 3% larger than the radius measured through the poles, the shorter axis approximately coincides with the axis of rotation
2.
Interstate 80 in California
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Interstate 80 is a major east–west route of the Interstate Highway System, running between the U. S. states of California and New York. The highway has its terminus in San Francisco. From there it heads east across the Bay Bridge to Oakland, I-80 then traverses the Sierra Nevada, cresting at Donner Summit, before crossing into the state of Nevada within the Truckee River Canyon. The speed limit is at most 65 miles per hour along the route instead of the states maximum of 70 mph. I-80 has portions designated as the Eastshore Freeway and Alan S. Hart Freeway, throughout California, I-80 was built along the corridor of U. S. Route 40, eventually replacing this designation entirely. The prior US40 corridor itself was built along several historic corridors in California, notably the California Trail, the route has changed from the original plans in San Francisco due to freeway revolts canceling segments of the originally planned alignment. Similarly in Sacramento, the freeway was re-routed around the city plans to upgrade the original grandfathered route through the city to Interstate highway standards were cancelled. I-80 is recognized as the Dwight D. Eisenhower Highway in the western United States, in California, it follows the original corridor of the Lincoln Highway from Sacramento to Reno. According to the California State Highway system, I-80 begins at its intersection with U. S. Route 101 in San Francisco, the Interstate designation is interpreted by some to actually beginning on the Bay Bridge approach itself, at the location of the Fremont Street off-ramp. Thus, the first 1.20 miles of the signed Interstate may not be officially an actual Interstate, the Eastshore Freeway is a segment of Interstates 80 and 580 along the northeast shoreline of San Francisco Bay in northern California. It begins at the Carquinez Bridge and ends at the MacArthur Maze interchange just east of the end of the San Francisco–Oakland Bay Bridge. Interstate 580 joins the Eastshore Freeway at an interchange known locally as the Hoffman Split in Albany. S, the Eastshore Highway began in El Cerrito at an intersection with San Pablo Avenue at Hill Street between Potrero Avenue and Cutting Blvd. Adjacent to the location today of the El Cerrito Del Norte station of BART and it was not a freeway in that access was at intersections with adjoining streets rather than by ramps. The Eastshore Highway ran from El Cerrito to the Bay Bridge along the routing as todays freeway. A causeway was constructed for this purpose by filling in part of the mudflats along the bayshore, the frontage road along the east side of todays Eastshore Freeway between Buchanan Street in Albany and Hearst Avenue in Berkeley retains the name Eastshore Highway. The terminal segment of the old Eastshore Highway in El Cerrito between Potrero and San Pablo Avenues is today named Eastshore Boulevard, originally, the name Eastshore Freeway was also applied to what is today known as the Nimitz Freeway upon its construction in 1947. This freeway was dedicated in 1958 to Admiral Nimitz, and so for a few years in the 1950s prior, until the late 1960s, the Eastshore Freeway was also designated as part of State Route 17 together with the Nimitz Freeway. The Eastshore Freeway was officially renamed the Kent D. Pursel Memorial Freeway in 1968, but this name is hardly recognized as such by the public, and most maps still show the name Eastshore Freeway
3.
Yerba Buena Island
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Yerba Buena Island sits in the San Francisco Bay between San Francisco and Oakland, California. The Yerba Buena Tunnel runs through its center and connects the western and eastern spans of the San Francisco–Oakland Bay Bridge and it has had several other names over the decades, Sea Bird Island, Wood Island, and Goat Island. The island is named after the town of Yerba Buena, which was named for the plant of the name that was abundant in the area. The plants English and Spanish common name, Yerba buena, is a form of the Spanish hierba buena. The island is part of District 6 of the City and County of San Francisco. According to the United States Census Bureau, Yerba Buena Island, today the military reservation southeast of the Yerba Buena Tunnel belongs to the United States Coast Guard District Eleven. The US Coast Guard Sector San Francisco – Vessel Traffic Service tower is located on Signal Road Bldg,278 atop the peak of the island. The US Coast Guard Sector San Francisco Headquarters is co-located with US Coast Guard Station San Francisco on Healy Avenue @ Fresnel Way at water-level on the southeast coast of the island, the USCG Station has a navigational buoy repair facility on Fresnel Way. The USCG Senior Officers residences are in Quarters A, B, C,8 and 9 off of Hillcrest Road on the hill atop the USCG base, the IOC houses the VTS, WatchKeeper and the US Coast Guard Sector San Francisco Command Center together in one building. Officially, the island was Yerba Buena Island until 1895, when on a decision by the United States Board on Geographic Names, during the gold rush, a large number of goats were pastured on the island, and the name Goat Island came into popular use. It was changed back to Yerba Buena Island on June 3,1931, in 1891, the United States Army Engineers built a Torpedo Station / Shed / Storehouse / Assembly building at the end of Army Road by North Gate Road. The torpedoes were actually floating mines that could be placed in the bay via cable for defense against intruding enemy vessels, the Torpedo Station was abandoned in the 1930s but still stands today listed in the National Register of Historic Places. Just before the turn of the 20th century, the first U. S. Naval Training Station on the Pacific Coast was established on the north east side of the island by 1st Street and North Gate Road. Quarters One, also known as the Admiral Nimitz House near the intersection of Whiting Way and its Classic Revival style, fashionable for private residences in the Bay Area at the time, was unusual for naval base housing. The training station closed after World War I, although the training station closed the Navy maintained presence with the stationary receiving ship USS Boston, later renamed USS Despatch, anchored in harbor through World War II. During World War II, Yerba Buena Island fell under the jurisdiction of Treasure Island Naval Station, built on the shoals of Yerba Buena Island, the 403-acre Treasure Island was a Works Progress Administration project in the 1930s. Quarters One became the residence of the Commander in Chief, US Pacific Fleet. Several other buildings used by the Naval Station during World War II also remain on the island, buildings 83,205 and 230 were support facilities to the senior officers quarters
4.
San Francisco Bay
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San Francisco Bay is a shallow estuary in the U. S. state of California. It is surrounded by a region known as the San Francisco Bay Area, dominated by the large cities San Francisco, Oakland. San Francisco Bay drains water from approximately 40 percent of California and it then connects to the Pacific Ocean via the Golden Gate strait. However, this group of interconnected bays is often called the San Francisco Bay. The bay was designated a Ramsar Wetland of International Importance on February 2,2013, the bay covers somewhere between 400 and 1,600 square miles, depending on which sub-bays, estuaries, wetlands, and so on are included in the measurement. The main part of the bay measures 3 to 12 miles wide east-to-west and it is the largest Pacific estuary in the Americas. Later, wetlands and inlets were filled in, reducing the Bays size since the mid-19th century by as much as one third. Recently, large areas of wetlands have been restored, further confusing the issue of the Bays size, despite its value as a waterway and harbor, many thousands of acres of marshy wetlands at the edges of the bay were, for many years, considered wasted space. As a result, soil excavated for building projects or dredged from channels was often dumped onto the wetlands, from the mid-19th century through the late 20th century, more than a third of the original bay was filled and often built on. The idea was, and remains, controversial, there are five large islands in San Francisco Bay. Alameda, the largest island, was created when a shipping lane was cut in 1901 and it is now predominantly a bedroom community. Angel Island was known as Ellis Island West because it served as the point for immigrants from East Asia. It is now a park accessible by ferry. Mountainous Yerba Buena Island is pierced by a tunnel linking the east and west spans of the San Francisco–Oakland Bay Bridge, attached to the north is the artificial and flat Treasure Island, site of the 1939 Golden Gate International Exposition. From the Second World War until the 1990s, both served as military bases and are now being redeveloped. Isolated in the center of the Bay is Alcatraz, the site of the federal penitentiary. The federal prison on Alcatraz Island no longer functions, but the complex is a popular tourist site, despite its name, Mare Island in the northern part of the bay is a peninsula rather than an island. During the last ice age, the now filled by the bay was a large linear valley with small hills
5.
San Francisco
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San Francisco, officially the City and County of San Francisco, is the cultural, commercial, and financial center of Northern California. It is the birthplace of the United Nations, the California Gold Rush of 1849 brought rapid growth, making it the largest city on the West Coast at the time. San Francisco became a consolidated city-county in 1856, after three-quarters of the city was destroyed by the 1906 earthquake and fire, San Francisco was quickly rebuilt, hosting the Panama-Pacific International Exposition nine years later. In World War II, San Francisco was a port of embarkation for service members shipping out to the Pacific Theater. Politically, the city votes strongly along liberal Democratic Party lines, San Francisco is also the headquarters of five major banking institutions and various other companies such as Levi Strauss & Co. Dolby, Airbnb, Weebly, Pacific Gas and Electric Company, Yelp, Pinterest, Twitter, Uber, Lyft, Mozilla, Wikimedia Foundation, as of 2016, San Francisco is ranked high on world liveability rankings. The earliest archaeological evidence of habitation of the territory of the city of San Francisco dates to 3000 BC. Upon independence from Spain in 1821, the became part of Mexico. Under Mexican rule, the system gradually ended, and its lands became privatized. In 1835, Englishman William Richardson erected the first independent homestead, together with Alcalde Francisco de Haro, he laid out a street plan for the expanded settlement, and the town, named Yerba Buena, began to attract American settlers. Commodore John D. Sloat claimed California for the United States on July 7,1846, during the Mexican–American War, montgomery arrived to claim Yerba Buena two days later. Yerba Buena was renamed San Francisco on January 30 of the next year, despite its attractive location as a port and naval base, San Francisco was still a small settlement with inhospitable geography. The California Gold Rush brought a flood of treasure seekers, with their sourdough bread in tow, prospectors accumulated in San Francisco over rival Benicia, raising the population from 1,000 in 1848 to 25,000 by December 1849. The promise of fabulous riches was so strong that crews on arriving vessels deserted and rushed off to the gold fields, leaving behind a forest of masts in San Francisco harbor. Some of these approximately 500 abandoned ships were used at times as storeships, saloons and hotels, many were left to rot, by 1851 the harbor was extended out into the bay by wharves while buildings were erected on piles among the ships. By 1870 Yerba Buena Cove had been filled to create new land, buried ships are occasionally exposed when foundations are dug for new buildings. California was quickly granted statehood in 1850 and the U. S. military built Fort Point at the Golden Gate, silver discoveries, including the Comstock Lode in Nevada in 1859, further drove rapid population growth. With hordes of fortune seekers streaming through the city, lawlessness was common, and the Barbary Coast section of town gained notoriety as a haven for criminals, prostitution, entrepreneurs sought to capitalize on the wealth generated by the Gold Rush
6.
Oakland, California
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Oakland /ˈoʊklənd/ is the largest city and the county seat of Alameda County, California, United States. The city was incorporated in 1852, Oaklands territory covers what was once a mosaic of California coastal terrace prairie, oak woodland, and north coastal scrub. Its land served as a resource when its hillside oak and redwood timber were logged to build San Francisco. In the late 1860s, Oakland was selected as the terminal of the Transcontinental Railroad. Following the 1906 San Francisco earthquake, many San Francisco citizens moved to Oakland, enlarging the citys population, increasing its housing stock and it continued to grow in the 20th century with its busy port, shipyards, and a thriving automobile manufacturing industry. Oakland is known for its sustainability practices, including a top-ranking for usage of electricity from renewable resources, in addition, due to a steady influx of immigrants during the 20th century, along with thousands of African-American war-industry workers who relocated from the Deep South during the 1940s. Oakland is the most ethnically diverse city in the country. The earliest known inhabitants were the Huchiun Indians, who lived there for thousands of years, the Huchiun belonged to a linguistic grouping later called the Ohlone. In Oakland, they were concentrated around Lake Merritt and Temescal Creek, in 1772, the area that later became Oakland was claimed, with the rest of California, by Spanish settlers for the King of Spain. In the early 19th century, the Spanish crown granted the East Bay area to Luis María Peralta for his Rancho San Antonio, the grant was confirmed by the successor Mexican republic upon its independence from Spain. Upon his death in 1842, Peralta divided his land among his four sons, Most of Oakland fell within the shares given to Antonio Maria and Vicente. The portion of the parcel that is now Oakland was called encinal—Spanish for oak grove—due to the oak forest that covered the area. In 1851, three men—Horace Carpentier, Edson Adams, and Andrew Moon—began developing what is now downtown Oakland, on May 4,1852, the Town of Oakland incorporated. Two years later, on March 25,1854, Oakland re-incorporated as the City of Oakland, with Horace Carpentier elected the first mayor, the city and its environs quickly grew with the railroads, becoming a major rail terminal in the late 1860s and 1870s. In 1868, the Central Pacific constructed the Oakland Long Wharf at Oakland Point, a number of horsecar and cable car lines were constructed in Oakland during the latter half of the 19th century. The first electric streetcar set out from Oakland to Berkeley in 1891, at the time of incorporation, Oakland consisted of the territory that lay south of todays major intersection of San Pablo Avenue, Broadway, and Fourteenth Street. The city gradually annexed farmlands and settlements to the east and the north, Oaklands rise to industrial prominence, and its subsequent need for a seaport, led to the digging of a shipping and tidal channel in 1902. This resulted in the town of Alameda being made an island
7.
State of California
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California is the most populous state in the United States and the third most extensive by area. Located on the western coast of the U. S, California is bordered by the other U. S. states of Oregon, Nevada, and Arizona and shares an international border with the Mexican state of Baja California. Los Angeles is Californias most populous city, and the second largest after New York City. The Los Angeles Area and the San Francisco Bay Area are the nations second- and fifth-most populous urban regions, California also has the nations most populous county, Los Angeles County, and its largest county by area, San Bernardino County. The Central Valley, an agricultural area, dominates the states center. What is now California was first settled by various Native American tribes before being explored by a number of European expeditions during the 16th and 17th centuries, the Spanish Empire then claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its war for independence. The western portion of Alta California then was organized as the State of California, the California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom. If it were a country, California would be the 6th largest economy in the world, fifty-eight percent of the states economy is centered on finance, government, real estate services, technology, and professional, scientific and technical business services. Although it accounts for only 1.5 percent of the states economy, the story of Calafia is recorded in a 1510 work The Adventures of Esplandián, written as a sequel to Amadis de Gaula by Spanish adventure writer Garci Rodríguez de Montalvo. The kingdom of Queen Calafia, according to Montalvo, was said to be a land inhabited by griffins and other strange beasts. This conventional wisdom that California was an island, with maps drawn to reflect this belief, shortened forms of the states name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, various estimates of the native population range from 100,000 to 300,000. The Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups also were diverse in their organization with bands, tribes, villages. Trade, intermarriage and military alliances fostered many social and economic relationships among the diverse groups, the first European effort to explore the coast as far north as the Russian River was a Spanish sailing expedition, led by Portuguese captain Juan Rodríguez Cabrillo, in 1542. Some 37 years later English explorer Francis Drake also explored and claimed a portion of the California coast in 1579. Spanish traders made unintended visits with the Manila galleons on their trips from the Philippines beginning in 1565
8.
California Department of Transportation
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The California Department of Transportation is an executive department within the U. S. state of California. Caltrans manages the highway system and is actively involved with public transportation systems throughout the state. It supports Amtrak California and the Capitol Corridor, the department is part of the state cabinet-level California State Transportation Agency. Like the majority of government agencies, Caltrans is headquartered in Sacramento. In 2015, Caltrans released a new statement, Provide a safe, sustainable, integrated and efficient transportation system to enhance California’s economy. The earliest predecessor of Caltrans was the Bureau of Highways, which was created by the California Legislature and this agency consisted of three commissioners who were charged with analyzing the state road system and making recommendations. At the time, there was no highway system, since roads were purely a local responsibility. After the commissioners submitted their report to the governor on November 25,1896, voters approved an $18 million bond issue for the construction of a state highway system in 1910, and the first Highway Commission was convened in 1911. On August 7,1912, the department broke ground on its first construction project, the year 1912 also saw the founding of the Transportation Laboratory and the creation of seven administrative divisions. In 1913, the legislature started requiring vehicle registration and allocated the funds to support regular highway maintenance. In 1921, the legislature turned the Department of Engineering into the Department of Public Works, the history of Caltrans and its predecessor agencies during the 20th century was marked by many firsts. In late 1972, the legislature approved a reorganization in which the Department of Public Works was merged with the Department of Aeronautics to become the modern Department of Transportation, for administrative purposes, Caltrans divides the State of California into 12 districts, supervised by district offices. Most districts cover multiple counties, District 12 is the district with one county. The largest districts by population are District 4 and District 7, like most state agencies, Caltrans maintains its headquarters in Sacramento, which is covered by District 3. Official California Department of Transportation website Named Highways, Freeways, Structures, and Other Appurtenances in California
9.
Suspension bridge
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A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. The first modern examples of type of bridge were built in the early 19th century. Simple suspension bridges, which lack vertical suspenders, have a history in many mountainous parts of the world. This type of bridge has cables suspended between towers, plus vertical suspender cables carry the weight of the deck below, upon which traffic crosses. This arrangement allows the deck to be level or to arc upward for additional clearance, like other suspension bridge types, this type often is constructed without falsework. The suspension cables must be anchored at each end of the bridge, the main cables continue beyond the pillars to deck-level supports, and further continue to connections with anchors in the ground. The roadway is supported by vertical suspender cables or rods, called hangers, in the latter case there will be very little arc in the outboard main cables. The earliest suspension bridges were ropes slung across a chasm, with a deck possibly at the level or hung below the ropes such that the rope had a catenary shape. The Tibetan saint and bridge-builder Thangtong Gyalpo originated the use of chains in his version of simple suspension bridges. In 1433, Gyalpo built eight bridges in eastern Bhutan, the last surviving chain-linked bridge of Gyalpos was the Thangtong Gyalpo Bridge in Duksum en route to Trashi Yangtse, which was finally washed away in 2004. Gyalpos iron chain bridges did not include a deck bridge which is the standard on all modern suspension bridges today. Instead, both the railing and the layer of Gyalpos bridges used wires. The stress points that carried the screed were reinforced by the iron chains, before the use of iron chains it is thought that Gyalpo used ropes from twisted willows or yak skins. He may have also used tightly bound cloth, the first American iron chain suspension bridge was the Jacobs Creek Bridge in Westmoreland County, Pennsylvania, designed by inventor James Finley. Finleys bridge was the first to all of the necessary components of a modern suspension bridge. Finley patented his design in 1808, and published it in the Philadelphia journal, The Port Folio, in 1810. Early British chain bridges included the Dryburgh Abbey Bridge and 137 m Union Bridge, with rapidly increasing to 176 m with the Menai Bridge. The first chain bridge on the European continent was the Chain Bridge in Nuremberg, the Clifton Suspension Bridge is one of the longest of the parabolic arc chain type
10.
Tunnel
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A tunnel is an underground passageway, dug through the surrounding soil/earth/rock and enclosed except for entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring methods, a tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. The central portions of a transit network are usually in tunnel. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers, utility tunnels are used for routing steam, chilled water, electrical power or telecommunication cables, as well as connecting buildings for convenient passage of people and equipment. Secret tunnels are built for military purposes, or by civilians for smuggling of weapons, contraband, special tunnels, such as wildlife crossings, are built to allow wildlife to cross human-made barriers safely. A tunnel is relatively long and narrow, the length is much greater than twice the diameter, although similar shorter excavations can be constructed. The definition of what constitutes a tunnel can vary widely from source to source, for example, the definition of a road tunnel in the United Kingdom is defined as a subsurface highway structure enclosed for a length of 150 metres or more. In the United States, the NFPA definition of a tunnel is An underground structure with a length greater than 23 m. The place where a road, railway, canal or watercourse passes under a footpath, cycleway, or another road or railway is most commonly called a bridge or, if passing under a canal, an aqueduct. Where it is important to stress that it is passing underneath, it may be called an underpass, a longer underpass containing a road, canal or railway is normally called a tunnel, whether or not it passes under another item of infrastructure. An underpass of any length under a river is usually called a tunnel. In the US, the term means an underground rapid transit system. Rail station platforms may be connected by tunnels or footbridges. Much of the technology of tunneling evolved from mining and military engineering. The etymology of the mining, military engineering, and civil engineering reveals these deep historic connections. A major tunnel project must start with an investigation of ground conditions by collecting samples from boreholes. An informed choice can then be made of machinery and methods for excavation and ground support, in planning the route, the horizontal and vertical alignments can be selected to make use of the best ground and water conditions. It is common practice to locate a tunnel deeper than otherwise would be required and this may be a particular concern in large-diameter tunnels
11.
Self-anchored suspension bridge
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A self-anchored suspension bridge is a suspension bridge in which the main cables attach to the ends of the deck, rather than to the ground via large anchorages. The design is well-suited for construction atop elevated piers, or in areas of soils where anchorages would be difficult to construct. The system balances forces internally without external anchorage requirements making it suitable for sites where large horizontal forces are difficult to anchor and this is similar to the method used in a tied-arch bridge where arch member compression is balanced by tension in the deck. The self-anchored suspension bridge form originated in the century, with a published description by Austrian engineer Josef Langer in 1859. Patent No.71,955 by American engineer Charles Bender in 1867, the form was applied to a handful of Rhine River crossings in Germany during the first half of the twentieth century. The Three Sisters Bridges of Pittsburgh are the earliest examples of this type in the US, other examples are Londons Chelsea Bridge. Previously the largest self-anchored suspension bridges are the Konohana Bridge in Japan, both of these bridges have a central span of 300 m. Because the primary cables cannot be anchored until the deck is completed
12.
Precast concrete
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In contrast, standard concrete is poured into site-specific forms and cured on site. Precast stone is distinguished from precast concrete using an aggregate in the mixture. Precast are only used within ranges of exterior and interior walls, compressed in concrete and stone, creating a solid but manuverable wall or face. By producing precast concrete in an environment, the precast concrete is afforded the opportunity to properly cure. Using a precast concrete system offers many advantages over onsite casting. Precast concrete production is performed on ground level, which helps with safety throughout a project, there is greater control over material quality and workmanship in a precast plant compared to a construction site. There are many different types of precast concrete forming systems for applications, differing in size, function. Stormwater drainage, water and sewage pipes, and tunnels make use of precast concrete units, the New South Wales Government Railways made extensive use of precast concrete construction for its stations and similar buildings. Between 1917 and 1932, they erected 145 such buildings, beyond cladding panels and structural elements, entire buildings can be assembled from precast concrete. Precast assembly enables fast completion of commercial shops and offices with minimal labor, for example, the Jim Bridger Building in Williston, North Dakota, was precast in Minnesota with air, electrical, water, and fiber utilities preinstalled into the building panels. The panels were transported over 800 miles to the Bakken oilfields, the building houses over 40,000 square feet of shops and offices. Virtually the entire building was fabricated in Minnesota, to complete the look of the four precast wall panel types — sandwich, plastered sandwich, inner layer and cladding panels — many surface finishes are available. Standard cement is white or grey, though different colors can be added with pigments or paints, the color and size of aggregate can also affect the appearance and texture of concrete surfaces. The shape and surface of the precast concrete molds have an effect on the look, The mold can be made of timber, steel, plastic, rubber or fiberglass, each material giving a unique finish. Ancient Roman builders made use of concrete and soon poured the material into moulds to build their network of aqueducts, is culverts. Modern uses for pre-cast technology include a variety of architectural and structural applications — including individual parts, in the modern world, precast panelled buildings were pioneered in Liverpool, England, in 1905. The process was invented by city engineer John Alexander Brodie, a genius who also invented the idea of the football goal net. The tram stables at Walton in Liverpool followed in 1906, the idea was not taken up extensively in Britain
13.
Segmental bridge
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As its name implies, a segmental bridge is a bridge built in short sections, i. e. one piece at a time, as opposed to traditional methods that build a bridge in very large sections. The bridge is made of concrete that is either cast-in-place or precast concrete and these bridges are very economical for long spans, especially when access to the construction site is restricted. They are also chosen for their aesthetic appeal, the first segmental concrete bridge, built in 1950, was cast-in-place across the Lahn River in Balduinstein, Germany. The first precast segmental concrete bridge, built in 1962, crossed the Seine River in France, the sequence of construction is similar to traditional concrete bridge building, i. e. build the support towers, build the temporary falsework, build the deck, perform finish work. The principal differences are as follows, The support towers may be built segmentally, often this is accomplished using slip-form construction, where the falsework moves upward following sequential concrete pours. The falsework uses the newly constructed concrete as the basis for moving upward, after the towers are built, a superstructure is built atop the towers. This superstructure serves as the point for building the deck. The deck is now constructed sequentially, beginning at the tower, in cast-in-place bridges, the falsework is connected to the previously installed concrete and allowed to cantilever freely. Next, the permanent reinforcing steel and supports are installed, finally, the concrete is placed and cured, freeing the falsework to be moved. In pre-cast bridges, the segment is constructed on the ground. As the new segment is suspended in place by the crane, each segment of the bridge designed to accept connections from both preceding and succeeding segments. The process in step 3 is repeated until the span is completed, linn Cove Viaduct in the Blue Ridge Mountains, North Carolina Manwel Dimech Bridge in St. Julians, Malta. This bridge connects the two parts of Regional Road and pass over Għomar Valley, portions of the Interstate 4 – Selmon Expressway Connector in Tampa, Florida LoBuono, J. Assembly required-The instructions for building New Jersey’s first segmental bridge
14.
Annual average daily traffic
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Annual average daily traffic, abbreviated AADT, is a measure used primarily in transportation planning and transportation engineering. Traditionally, it is the volume of vehicle traffic of a highway or road for a year divided by 365 days. AADT is a useful and simple measurement of how busy the road is, newer advances from traffic data providers are now providing AADT by side of the road, by day of week and by time of day. One of the most important uses of AADT is for determining funding for the maintenance, in the United States the amount of federal funding a state will receive is related to the total traffic measured across its Highway network. Each year on June 15, every state in the United States submits a Highway Performance Monitoring System HPMS report, the HPMS report contains various information regarding the road segments in the state based on a sample of the road segments. In the report, the AADT is converted to Vehicle Miles Traveled, VMT is the AADT multiplied by the length of the road segment. To determine the amount of traffic a state has, the AADT cannot be summed for all road segments since an AADT is a rate, the VMT is summed and is used as an indicator of the amount of traffic a state has. For federal-funding, formulas are applied to include the VMT and other highway statistics, to measure AADT on individual road segments, traffic data is collected either by an automated traffic counter or hiring an observer to record traffic. There are two different techniques of measuring the AADTs for road segments, one technique is called continuous count data collection method. This is where sensors are embedded into a road and traffic data is measured all 365 days. The AADT would be the sum of the traffic for the entire year divided by 365 days. There is a problem calculating the AADT with this method. The continuous count equipment is not operating for the full 365 days due to being shut down for maintenance or repair, because of this, seasonal or day-of-week biases might skew the calculated AADT. In 1992, AASHTO released the AASHTO Guidelines for Traffic Data Programs, for every month and day-of-week, a Monthly Average Day of Week is calculated. Each day-of-weeks MADW is then calculated across months to calculate an Annual Average Day of Week, finally, the AADWs are averaged to calculate an AADT. The United States Federal Highway Administration has adopted this method as the method in the. While providing the most accurate AADT, installing and maintaining continuous count stations method is costly, most agencies are only able to monitor a very small percentage of the roadway using this method. Most AADTs are generated using data collection methods sometimes known as the coverage count data collection method
15.
National Register of Historic Places
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The National Register of Historic Places is the United States federal governments official list of districts, sites, buildings, structures, and objects deemed worthy of preservation. The passage of the National Historic Preservation Act in 1966 established the National Register, of the more than one million properties on the National Register,80,000 are listed individually. The remainder are contributing resources within historic districts, each year approximately 30,000 properties are added to the National Register as part of districts or by individual listings. For most of its history the National Register has been administered by the National Park Service and its goals are to help property owners and interest groups, such as the National Trust for Historic Preservation, coordinate, identify, and protect historic sites in the United States. While National Register listings are mostly symbolic, their recognition of significance provides some financial incentive to owners of listed properties, protection of the property is not guaranteed. During the nomination process, the property is evaluated in terms of the four criteria for inclusion on the National Register of Historic Places, the application of those criteria has been the subject of criticism by academics of history and preservation, as well as the public and politicians. Occasionally, historic sites outside the proper, but associated with the United States are also listed. Properties can be nominated in a variety of forms, including individual properties, historic districts, the Register categorizes general listings into one of five types of properties, district, site, structure, building, or object. National Register Historic Districts are defined geographical areas consisting of contributing and non-contributing properties, some properties are added automatically to the National Register when they become administered by the National Park Service. These include National Historic Landmarks, National Historic Sites, National Historical Parks, National Military Parks/Battlefields, National Memorials, on October 15,1966, the Historic Preservation Act created the National Register of Historic Places and the corresponding State Historic Preservation Offices. Initially, the National Register consisted of the National Historic Landmarks designated before the Registers creation, approval of the act, which was amended in 1980 and 1992, represented the first time the United States had a broad-based historic preservation policy. To administer the newly created National Register of Historic Places, the National Park Service of the U. S. Department of the Interior, hartzog, Jr. established an administrative division named the Office of Archeology and Historic Preservation. Hartzog charged OAHP with creating the National Register program mandated by the 1966 law, ernest Connally was the Offices first director. Within OAHP new divisions were created to deal with the National Register, the first official Keeper of the Register was William J. Murtagh, an architectural historian. During the Registers earliest years in the late 1960s and early 1970s, organization was lax and SHPOs were small, understaffed, and underfunded. A few years later in 1979, the NPS history programs affiliated with both the U. S. National Parks system and the National Register were categorized formally into two Assistant Directorates. Established were the Assistant Directorate for Archeology and Historic Preservation and the Assistant Directorate for Park Historic Preservation, from 1978 until 1981, the main agency for the National Register was the Heritage Conservation and Recreation Service of the United States Department of the Interior. In February 1983, the two assistant directorates were merged to promote efficiency and recognize the interdependency of their programs, jerry L. Rogers was selected to direct this newly merged associate directorate
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California
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California is the most populous state in the United States and the third most extensive by area. Located on the western coast of the U. S, California is bordered by the other U. S. states of Oregon, Nevada, and Arizona and shares an international border with the Mexican state of Baja California. Los Angeles is Californias most populous city, and the second largest after New York City. The Los Angeles Area and the San Francisco Bay Area are the nations second- and fifth-most populous urban regions, California also has the nations most populous county, Los Angeles County, and its largest county by area, San Bernardino County. The Central Valley, an agricultural area, dominates the states center. What is now California was first settled by various Native American tribes before being explored by a number of European expeditions during the 16th and 17th centuries, the Spanish Empire then claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its war for independence. The western portion of Alta California then was organized as the State of California, the California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom. If it were a country, California would be the 6th largest economy in the world, fifty-eight percent of the states economy is centered on finance, government, real estate services, technology, and professional, scientific and technical business services. Although it accounts for only 1.5 percent of the states economy, the story of Calafia is recorded in a 1510 work The Adventures of Esplandián, written as a sequel to Amadis de Gaula by Spanish adventure writer Garci Rodríguez de Montalvo. The kingdom of Queen Calafia, according to Montalvo, was said to be a land inhabited by griffins and other strange beasts. This conventional wisdom that California was an island, with maps drawn to reflect this belief, shortened forms of the states name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, various estimates of the native population range from 100,000 to 300,000. The Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups also were diverse in their organization with bands, tribes, villages. Trade, intermarriage and military alliances fostered many social and economic relationships among the diverse groups, the first European effort to explore the coast as far north as the Russian River was a Spanish sailing expedition, led by Portuguese captain Juan Rodríguez Cabrillo, in 1542. Some 37 years later English explorer Francis Drake also explored and claimed a portion of the California coast in 1579. Spanish traders made unintended visits with the Manila galleons on their trips from the Philippines beginning in 1565
17.
Interstate 80 (California)
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Interstate 80 is a major east–west route of the Interstate Highway System, running between the U. S. states of California and New York. The highway has its terminus in San Francisco. From there it heads east across the Bay Bridge to Oakland, I-80 then traverses the Sierra Nevada, cresting at Donner Summit, before crossing into the state of Nevada within the Truckee River Canyon. The speed limit is at most 65 miles per hour along the route instead of the states maximum of 70 mph. I-80 has portions designated as the Eastshore Freeway and Alan S. Hart Freeway, throughout California, I-80 was built along the corridor of U. S. Route 40, eventually replacing this designation entirely. The prior US40 corridor itself was built along several historic corridors in California, notably the California Trail, the route has changed from the original plans in San Francisco due to freeway revolts canceling segments of the originally planned alignment. Similarly in Sacramento, the freeway was re-routed around the city plans to upgrade the original grandfathered route through the city to Interstate highway standards were cancelled. I-80 is recognized as the Dwight D. Eisenhower Highway in the western United States, in California, it follows the original corridor of the Lincoln Highway from Sacramento to Reno. According to the California State Highway system, I-80 begins at its intersection with U. S. Route 101 in San Francisco, the Interstate designation is interpreted by some to actually beginning on the Bay Bridge approach itself, at the location of the Fremont Street off-ramp. Thus, the first 1.20 miles of the signed Interstate may not be officially an actual Interstate, the Eastshore Freeway is a segment of Interstates 80 and 580 along the northeast shoreline of San Francisco Bay in northern California. It begins at the Carquinez Bridge and ends at the MacArthur Maze interchange just east of the end of the San Francisco–Oakland Bay Bridge. Interstate 580 joins the Eastshore Freeway at an interchange known locally as the Hoffman Split in Albany. S, the Eastshore Highway began in El Cerrito at an intersection with San Pablo Avenue at Hill Street between Potrero Avenue and Cutting Blvd. Adjacent to the location today of the El Cerrito Del Norte station of BART and it was not a freeway in that access was at intersections with adjoining streets rather than by ramps. The Eastshore Highway ran from El Cerrito to the Bay Bridge along the routing as todays freeway. A causeway was constructed for this purpose by filling in part of the mudflats along the bayshore, the frontage road along the east side of todays Eastshore Freeway between Buchanan Street in Albany and Hearst Avenue in Berkeley retains the name Eastshore Highway. The terminal segment of the old Eastshore Highway in El Cerrito between Potrero and San Pablo Avenues is today named Eastshore Boulevard, originally, the name Eastshore Freeway was also applied to what is today known as the Nimitz Freeway upon its construction in 1947. This freeway was dedicated in 1958 to Admiral Nimitz, and so for a few years in the 1950s prior, until the late 1960s, the Eastshore Freeway was also designated as part of State Route 17 together with the Nimitz Freeway. The Eastshore Freeway was officially renamed the Kent D. Pursel Memorial Freeway in 1968, but this name is hardly recognized as such by the public, and most maps still show the name Eastshore Freeway
18.
List of longest suspension bridge spans
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The worlds longest suspension bridges are listed according to the length of their main span. If one bridge has a longer span than another it does not necessarily mean that the bridge is longer from shore to shore, suspension bridges have the longest spans of any type of bridge. Cable-stayed bridges, the next longest design, are practical for spans up to just over 1 kilometre, therefore, the 17 longest bridges on this list are all currently the 17 longest spans of all types of vehicular bridges. This list includes only completed suspension bridges that carry automobiles or trains and it does not include cable-stayed bridges, footbridges, or pipeline bridges. Most of the suspension bridges built in recent years have been in the Peoples Republic of China. As the following list shows, most of the bridges under construction are also in China, sources, Si Du River Bridge 2009 The highest bridge in the world. San Francisco – Oakland Bay Bridge, the widest bridge in the world is also the most expensive bridge and the largest self-anchored suspension bridge ever constructed. Tacoma Narrows Bridges 853 m—1950 &2007, the pair of bridges with the longest spans in the world. The longest span carrying road and rail traffic, suspension bridge with the most lanes of traffic. Structural steel designers handbook, AISC, AASHTO, AISI, ASTM, AREMA, —includes a list of major suspension bridges by length Progress of Center Span on Long-Span Bridges at the Honshū—Shikoku Bridge Expressway Co
19.
Toll bridge
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A toll bridge is a bridge over which traffic may pass upon payment of a toll, or fee. The practice of collecting tolls on bridges harks back to the days of ferry crossings where people paid a fee to be ferried across stretches of water, as boats became impractical to carry large loads, ferry operators looked for new sources of revenue. Having built a bridge, they hoped to recoup their investment by charging tolls for people, animals, vehicles, and goods to cross it. The original London Bridge across the river Thames opened as a toll bridge, using interest on its capital assets, the trust now owns and runs all seven central London bridges at no cost to taxpayers or users. In the United States, private ownership of toll bridges peaked in the mid-19th century, in some instances, a quasi-governmental authority was formed, and toll revenue bonds were issued to raise funds for construction and/or operation of the facility. Peters and Kramer observed that. little research has been done to quantify the impact of collection on society as a whole. And therefore they published an analysis of the Total Societal Cost associated with toll collection as a means of taxation. TSC is the sum of administrative, compliance, fuel and pollution costs, in 2000 they estimated it to be $56,914,732, or 37. 3% of revenue collected. Nakamura and Kockelman show that tolls are by nature regressive, shifting the burden of taxation disproportionately to the poor and middle classes. Electronic toll collection, branded under names such as EZ-Pass, SunPass, IPass, FasTrak, Treo, GoodToGo, electronic tolling proposals that represented the shadow price of electronic toll collection may have misled decision makers. Consumers have additionally endured an increased administrative burden associated with paying toll bills, additionally, visitors to a region may incur e-toll tag fees imposed by their rental car company. The Paperwork Reduction Act of 1980 identified and attempted to address a problem associated with the government collection of information. Approvals were to be secured by government agencies before promulgating a paper form, website, however, the act did not anticipate and thus address the consumer burden associated with funding infrastructure via electronic toll collection instead of through more traditional forms of taxation. In some instances, tolls have been removed after retirement of the toll revenue bonds issued to raise funds for construction and/or operation of the facility, sometimes citizens revolt against toll plazas, as was the case in Jacksonville, Florida. Tolls were in place on four bridges crossing the St. Johns River and these tolls paid for the respective bridges as well as many other highway projects. As Jacksonville continued to grow, the tolls created bottlenecks on the roadway, in 1988, Jacksonville voters chose to eliminate all the toll booths and replace the revenue with a ½ cent sales tax increase. In 1989, the booths were removed,36 years after the first toll booth went up. In Scotland, the Scottish Parliament purchased the Skye Bridge from its owners in late 2004, in 2004, the German government cancelled a contract with the Toll Collect syndicate after much negative publicity
20.
California Gold Rush
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The California Gold Rush began on January 24,1848, when gold was found by James W. Marshall at Sutters Mill in Coloma, California. The news of gold brought some 300,000 people to California from the rest of the United States, the Gold Rush initiated the California Genocide, with 100,000 Native Californians dying between 1848 and 1868. By the time it ended, California had gone from a thinly populated ex-Mexican territory to the state of the first nominee for the Republican Party. The effects of the Gold Rush were substantial, whole indigenous societies were attacked and pushed off their lands by the gold-seekers, called forty-niners. The first to hear confirmed information of the rush were the people in Oregon, the Sandwich Islands, and Latin America. While most of the newly arrived were Americans, the Gold Rush attracted tens of thousands from Latin America, Europe, Australia, agriculture and ranching expanded throughout the state to meet the needs of the settlers. San Francisco grew from a settlement of about 200 residents in 1846 to a boomtown of about 36,000 by 1852. Roads, churches, schools and other towns were built throughout California, in 1849 a state constitution was written. The new constitution was adopted by vote, and the future states interim first governor. In September,1850, California became a state, at the beginning of the Gold Rush, there was no law regarding property rights in the goldfields and a system of staking claims was developed. Prospectors retrieved the gold from streams and riverbeds using simple techniques, although the mining caused environmental harm, more sophisticated methods of gold recovery were developed and later adopted around the world. New methods of transportation developed as steamships came into regular service, by 1869 railroads were built across the country from California to the eastern United States. At its peak, technological advances reached a point where significant financing was required, Gold worth tens of billions of todays dollars was recovered, which led to great wealth for a few. However, many returned home with more than they had started with. The Mexican–American War ended on February 3,1848, although California was firmly in American hands before that, the Treaty of Guadalupe Hidalgo provided for, among other things, the formal transfer of Upper California to the United States. The California Gold Rush began at Sutters Mill, near Coloma, on January 24,1848, James W. Marshall, a foreman working for Sacramento pioneer John Sutter, found shiny metal in the tailrace of a lumber mill Marshall was building for Sutter on the American River. Marshall brought what he found to John Sutter, and the two tested the metal. However, rumors started to spread and were confirmed in March 1848 by San Francisco newspaper publisher
21.
American Bridge Company
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The American Bridge Company is a civil engineering firm that specializes in building and renovating bridges and other large civil engineering projects. Founded in 1900, the company is headquartered in Coraopolis, Pennsylvania, the firm has built many bridges in the U. S. and elsewhere, the Historic American Engineering Record notes at least 81. American Bridge has also built or helped build the Willis Tower, the Empire State Building, the Chrysler Building, launch pads, resorts, during World War II, it produced tank landing ships for the United States Navy. Competitors include Walsh Group, Flatiron Construction, and Skanska USA, related companies include American Bridge Holding Company and American Bridge Manufacturing Company, both also headquartered in Coraopolis. American Bridge Company was founded in April 1900, when JP Morgan led a consolidation of 28 of the largest U. S. steel fabricators and constructors, in 1902, the company became a subsidiary of United States Steel as part of the Steel Trust consolidation. It went on to do work across the nation and around the world, during World War II, the company built warships for the U. S. Navy. In 1944, American painter Thomas Hart Benton recorded the construction and launch of LST768, producing numerous drawings, the company went private in 1987 and was sold to Continental Engineering Corporation in 1988. The town of Ambridge, Pennsylvania, was an American Bridge company town, both municipalities are on the Ohio River near Pittsburgh, with access to many steel suppliers, as well as to waterborne and rail transport, to allow shipment of components and subassemblies. This is a representative, not an exhaustive, list, orinoco Bridge, Venezuela 25th of April Bridge, Lisbon, Portugal Built the worlds longest arch bridge on three occasions. 25 April Bridge in Lisbon, Portugal First stiffening truss replacement on a loaded, lions Gate Bridge, Vancouver, British Columbia, Canada The ongoing Eastern span replacement of the San Francisco–Oakland Bay Bridge, in a joint venture with Fluor Corporation, American Bridge-Fluor. Built the world’s tallest building on numerous occasions, john Hancock Center, Chicago Aon Center, Chicago Columbia Seafirst Center, Seattle U. S. Steel Tower,1970 Flatiron Building, New York City,1902 Built the world’s largest building by volume twice. Hammerhead Crane, 350ton Cantilever type, Cardwell v. American Bridge Co, news article on American Bridge legacy Another article on legacy
22.
Golden Gate Bridge
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The Golden Gate Bridge is a suspension bridge spanning the Golden Gate strait, the one-mile-wide, one-point-seven-mile-long channel between San Francisco Bay and the Pacific Ocean. The bridge is one of the most internationally recognized symbols of San Francisco, California, and it has been declared one of the Wonders of the Modern World by the American Society of Civil Engineers. The Frommers travel guide describes the Golden Gate Bridge as possibly the most beautiful, certainly the most photographed and it opened in 1937 and was, until 1964, the longest suspension bridge main span in the world, at 4,200 feet. Before the bridge was built, the only practical short route between San Francisco and what is now Marin County was by boat across a section of San Francisco Bay. A ferry service began as early as 1820, with a scheduled service beginning in the 1840s for the purpose of transporting water to San Francisco. Once for railroad passengers and customers only, Southern Pacifics automobile ferries became very profitable, the trip from the San Francisco Ferry Building took 27 minutes. Many wanted to build a bridge to connect San Francisco to Marin County, San Francisco was the largest American city still served primarily by ferry boats. Because it did not have a permanent link with communities around the bay, experts said that ferocious winds and blinding fogs would prevent construction and operation. San Franciscos City Engineer estimated the cost at $100 million, which would have been $2.12 billion in 2009 and he asked bridge engineers whether it could be built for less. One who responded, Joseph Strauss, was an engineer and poet who had, for his graduate thesis. At the time, Strauss had completed some 400 drawbridges—most of which were inland—and nothing on the scale of the new project. Strausss initial drawings were for a massive cantilever on each side of the strait, connected by a central suspension segment, Local authorities agreed to proceed only on the assurance that Strauss would alter the design and accept input from several consulting project experts. A suspension-bridge design was considered the most practical, because of recent advances in metallurgy, Strauss spent more than a decade drumming up support in Northern California. The bridge faced opposition, including litigation, from many sources, the Department of War was concerned that the bridge would interfere with ship traffic. The navy feared that a collision or sabotage to the bridge could block the entrance to one of its main harbors. Unions demanded guarantees that local workers would be favored for construction jobs, in May 1924, Colonel Herbert Deakyne held the second hearing on the Bridge on behalf of the Secretary of War in a request to use federal land for construction. Another ally was the automobile industry, which supported the development of roads. The bridges name was first used when the project was discussed in 1917 by M. M
23.
Interurban streetcar
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The interurban is a type of electric railway, with streetcar-like light electric self-propelled railcars which run within and between cities or towns. They were prevalent in North America between 1900 and 1925 and were used primarily for travel between cities and their surrounding suburban and rural communities. Limited examples existed in Europe and Asia, Interurban as a term encompassed the companies, their infrastructure, and the cars that ran on the rails. The interurban, especially in the United States, was a cultural institution. Most roads and town streets were unpaved, and transportation was by horse-drawn carriages, the interurban provided vital transportation links between the city and countryside. In 1915,15,500 miles of railways were operating in the United States. For a time, interurban railways were the fifth-largest industry in the United States, by 1930, most interurbans were gone, with few surviving into the 1950s. The term interurban was coined by Charles L. Henry, a senator in Indiana. The Latin, inter urbes, means between cities, the interurban fit on a continuum between urban street railways and full-fledged railroads. George W. Hilton and John F, Due identified four characteristics of an interurban, Electric power for propulsion. Passenger service as the primary business, equipment heavier and faster than urban streetcars. Operation on tracks in city streets, and in areas on roadside tracks or private right-of-way. The definition of interurban is necessarily blurry, there was a large amount of consolidation of lines following initial construction. In 1905 the United States Census Bureau defined an interurban as a railway having more than half its trackage outside municipal limits. It drew a distinction between interurban and suburban railroads, a suburban system was oriented toward a city center in a single urban area and served commuter traffic. A regular railroad moved riders from one city center to city center. The typical interurban similarly served more than one city, but it served a smaller region and made frequent stops. The 1880s and saw the first successful deployments of electric traction in streetcar systems, most of these built on the pioneering work of Frank J. Sprague, who developed an improved method for mounting an electric traction motor and using a trolley pole for pickup
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Key System
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The KeY tool is used in formal verification of Java programs. It accepts specifications written in the Java Modeling Language to Java source files and these are transformed into theorems of dynamic logic and then compared against program semantics that are likewise defined in terms of dynamic logic. KeY is significantly powerful in that it supports both interactive and fully automated correctness proofs, failed proof attempts can be used for a more efficient debugging or verification-based testing. There have been extensions to KeY in order to apply it to the verification of C programs or hybrid systems. The usual user input to KeY consists of a Java source file with annotations in JML, both are translated to KeYs internal representation, dynamic logic. From the given specifications, several proof obligations arise which are to be discharged, to this ends, the program is symbolically executed with the resulting changes to program variables stored in so-called updates. Once the program has been processed completely, there remains a first-order logic proof obligation, at the heart of the KeY system lies a first-order theorem prover based on sequent calculus, which is used to close the proof. Interference rules are captured in so called taclets which consist of an own language to describe changes to a sequent. The theoretical foundation of KeY is a formal logic called Java Card DL and it is a version of a first-order dynamic logic tailored to Java Card programs. This is equivalent to α in Hoare calculus if ϕ and ψ are purely first order, dynamic logic, however, extends Hoare logic in that formulas may contain nested program modalities such as, or that quantification over formulas which contain modalities is possible. There is also a dual modality ⟨ α ⟩ which includes termination and this dynamic logic can be seen as a special multi-modal logic where for each Java block α there are modalities and ⟨ α ⟩. At the heart of the KeY system lies a first-order theorem prover based on a sequent calculus. A sequent is of the form Γ ⊢ Δ where Γ and Δ are sets of formulas with the meaning that ⋀ γ ∈ Γ γ → ⋁ δ ∈ Δ δ holds true. By means of deduction, an initial sequent representing the obligation is shown to be constructible from just fundamental first-order axioms. During that, program modalities are eliminated by symbolic execution, for instance, the formula x = ˙0 → x = ˙1 is logically equivalent to x = ˙0 → x = ˙0. As this example shows, symbolic execution in dynamic logic is similar to calculating weakest preconditions. Both ψ and w p essentially denote the same thing – with two exceptions, Firstly, w p is a function of some meta-calculus while ψ really is a formula of the given calculus, secondly, symbolic execution runs through the program forward just as an actual execution would. To save intermediate results of assignments, KeY introduces a concept called updates, syntactically, updates are consist of parallel assignments written in curly braces in front of a modality
25.
James Rolph
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James “Sunny Jim” Rolph Jr. was an American politician and a member of the Republican Party. He was elected to a term as the 27th governor of California from January 6,1931 until his death on June 2,1934 at the height of the Great Depression. Previously, Rolph had been the 30th mayor of San Francisco from January 8,1912 until his resignation to become governor, Rolph remains the longest serving mayor in San Francisco history. Rolph was born in San Francisco and he had four brothers and two sisters. After attending school in the Mission District, he went to work as a boy in a commission house. He married Annie Marshall Reid and had at least one son, James Rolph, Rolph entered the shipping business in 1900, by forming a partnership with George Hind. He would over the next serve as president of two banks, one of which he helped establish. Although he was asked to run for mayor in 1909, he chose to wait until 1911 to run for mayor—a position that he would hold for nineteen years, as mayor, he was known as Sunny Jim and his theme song was There Are Smiles That Make You Happy. In 1915 he appeared as himself in a documentary film titled Mabel and Fatty Viewing the Worlds Fair at San Francisco. In 1924, Rolph appeared as himself in a Slim Summerville comedy short film, Hello, Rolph knew of the power in San Francisco of the Roman Catholic Church. Italians, Irish, French and Germans made up the majority of the population of the City and he established a deep friendship with Archbishop Edward Joseph Hanna. In turn, Hanna would support Rolph in his 1930 election as governor of California, in addition to his mayoral duties and overseeing his shipping interests, he directed the Ship Owners and Merchants Tugboat Company and the San Francisco Chamber of Commerce. He also was vice-president of the Panama-Pacific International Exposition and president of the Merchants Exchange and he resigned in 1931 to assume the office of governor of California. Four days before the lynching he had announced he would not call on the National Guard to prevent the lynching, after violence erupted during the San Joaquin cotton strike in October 1933, Governor Rolph appointed a fact-finding committee to investigate the deaths of several strikers. After suffering several heart attacks, he died in Santa Clara County on June 2,1934, aged 64, Rolph was the second governor to die in office, the first being Washington Bartlett in 1887. He is buried at Greenlawn Memorial Park in Colma, California and he was succeeded by Lieutenant Governor Frank Merriam in the Governors Office. One of the names of the San Francisco–Oakland Bay Bridge is the James “Sunny Jim” Rolph Bridge. Biography from the State of California James Rolph, Jr. at The Political Graveyard Biography from the Virtual Museum of the City of San Francisco James Rolph at the Internet Movie Database
26.
Mayor of San Francisco
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The Mayor of the City and County of San Francisco is the head of the executive branch of the San Francisco city and county government. The mayor has the duty to enforce city laws, and the power to approve or veto bills passed by the San Francisco Board of Supervisors. The mayor serves a term and is limited to two successive terms. There have been 42 individuals sworn into office, john W. Geary, elected in 1850, was the first mayor of the city. Charles James Brenham, who served as mayor during the 1850s, is the person who has served two non-consecutive terms. The previous mayor, Gavin Newsom resigned to become the Lieutenant Governor of California on January 10,2011, Ed Lee was appointed by the Board of Supervisors on the following day to finish out Newsoms term. Lee was elected to his own term on November 8,2011, the mayor of San Francisco is elected every four years, elections take place one year before United States presidential elections on election day in November. Candidates must live and be registered to vote in San Francisco at the time of the election, the mayor is usually sworn in on the January 8 following the election. The next election for the mayor will be in 2019, under the California constitution, all city elections in the state are conducted on a non-partisan basis. As a result, candidates party affiliations are not listed on the ballot, mayoral elections were originally run under a two-round system. If no candidate received a majority of votes in the general election. In 2002, the system for city officials was overhauled as a result of a citywide referendum. The new system, known as instant-runoff voting, allows voters to select, if no one wins more than half of the first-choice votes, the candidate with the fewest votes is eliminated and second-choice votes are counted until a candidate captures the majority. This eliminates the need to hold a separate runoff election and saves money and this was first implemented in the 2004 Board of Supervisors election after two years of preparation. In 2007, the new system was implemented in the election for the first time. To date,42 individuals have served as mayor, there have been 43 mayoralties due to Charles James Brenhams serving two non-consecutive terms, he is counted chronologically as both the second and fourth mayor. The longest term was that of James Rolph, who served over 18 years until his resignation to become the California governor, the length of his tenure as mayor was largely due to his popularity. During his term, San Francisco saw the expansion of its system, the construction of the Civic Center
27.
List of Speakers of the California State Assembly
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This is a list of Speakers of the California State Assembly. It does not number those individuals who serving abbreviated terms, nor those serving during a session called by the Governor for a narrowly defined agenda. Office of the Chief Clerk of the Assembly, archived from the original on June 20,2007
28.
Willie Brown (politician)
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Willie Lewis Brown, Jr. is an American politician of the Democratic Party. He served over 30 years in the California State Assembly, spending 15 years as its speaker, and later served as the 41st mayor of San Francisco, the first African American to do so. Under the current California term-limits law, no Speaker of the California State Assembly will be permitted to have a longer tenure than Browns, the San Francisco Chronicle called Brown one of San Franciscos most notable mayors who had celebrity beyond the citys boundaries. Brown was born in Mineola, Texas and graduated from Mineola Colored High School in 1951 and he moved to San Francisco in 1951, attending San Francisco State University and graduating in 1955 with a degree in liberal studies. Brown earned a J. D. from University of California and he spent several years in private practice before gaining election in his second attempt to the California Assembly in 1964. Brown became the Democrats whip in 1969 and speaker in 1980 and he was known for his ability to manage people and maintain party discipline. According to The New York Times, Brown became one of the countrys most powerful state legislators and his long tenure and powerful position were used as a focal point of Californias initiative campaign to limit the terms of state legislators, which passed in 1990. During the last of his three allowed post-initiative terms, Brown maintained control of the Assembly despite a slim Republican majority by gaining the vote of several Republicans, near the end of his final term, Brown left the legislature to become mayor of San Francisco. Brown served as San Francisco mayor from January 8,1996 until January 8,2004 and his tenure as mayor is marked by a significant increase in real estate development, public works, city beautification, and other large-scale city projects. He presided over the era at a time when San Franciscos economy was rapidly expanding. Brown presided over the city’s most diverse administration with more Asian Americans, women, Latinos, gays and he increased San Franciscos funding of Muni by tens of millions of dollars and ended the citys policy of punishing people for feeding the homeless. The SF Board of Supervisors opposed Browns agenda and some of his initiatives, in particular office, Brown was restricted by term limits from running for mayor and was succeeded by a political protege, Gavin Newsom. Brown was born in Mineola, a segregated town in east Texas marked by racial tensions, to Minnie Collins Boyd. Brown was the fourth of five children, during Browns childhood, mob violence periodically erupted in Mineola, keeping African Americans from voting. His first job was as a boy in a whites-only barber shop. He later worked as a janitor, fry cook, and field hand and he learned his work ethic at a young age from his grandmother. He graduated from MacFarland High School, a school he later described as substandard. Brown originally wanted to attend Stanford University and his interviewer from Stanford also taught at San Francisco State and was surprised by Brown’s ambition
29.
Cantilever bridge
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A cantilever bridge is a bridge built using cantilevers, structures that project horizontally into space, supported on only one end. Engineers in the nineteenth century understood that a bridge that was continuous across multiple supports would distribute the loads among them and this would result in lower stresses in the girder or truss and meant that longer spans could be built. Several nineteenth century engineers patented continuous bridges with hinge points mid-span, the use of a hinge in the multi-span system presented the advantages of a statically determinate system and of a bridge that could handle differential settlement of the foundations. Engineers could more easily calculate the forces and stresses with a hinge in the girder, heinrich Gerber was one of the engineers to obtain a patent for a hinged girder and is recognized as the first to build one. The Hassfurt Bridge over the Main river in Germany with a span of 124 feet was completed in 1867 and is recognized as the first modern cantilever bridge. The High Bridge of Kentucky by C, the Kentucky River Bridge spanned a gorge that was 275 feet deep and took full advantage of the fact that falsework, or temporary support, is not needed for the main span of a cantilever bridge. The most famous early cantilever bridge is the Forth Bridge and this bridge held the record for longest span in the world for seventeen years, until it was surpassed by the Quebec Bridge. Benjamin Baker illustrated the principles of the suspended span cantilever in the photo on the left. The suspended span, where Kaichi Watanabe sits, is seen in the center, the need to resist compression of the lower chord is seen in the use of wooden poles while the tension of the upper chord is shown by the outstretched arms. The action of the foundations as anchors for the cantilever is visible in the placement of the counterweights. A simple cantilever span is formed by two arms extending from opposite sides of an obstacle to be crossed, meeting at the center. In a common variant, the span, the cantilever arms do not meet in the center, instead. The suspended span may be built off-site and lifted into place, thus, in a bridge built on two foundation piers, there are four cantilever arms, two which span the obstacle, and two anchor arms which extend away from the obstacle. Because of the need for strength at the balanced cantilevers supports. The Commodore Barry Bridge is an example of type of cantilever bridge. Steel truss cantilevers support loads by tension of the upper members, commonly, the structure distributes the tension via the anchor arms to the outermost supports, while the compression is carried to the foundations beneath the central towers. Many truss cantilever bridges use pinned joints and are statically determinate with no members carrying mixed loads. Prestressed concrete balanced cantilever bridges are built using segmental construction
30.
1989 Loma Prieta earthquake
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The 1989 Loma Prieta earthquake occurred in Northern California on October 17 at 5,04 p. m. local time. With a moment magnitude of 6.9 and a maximum Mercalli intensity of IX, no surface faulting occurred, though a large number of other ground failures and landslides were present, especially in the Summit area of the Santa Cruz Mountains. Due to the coverage of the 1989 World Series, it became the first major earthquake in the United States that was broadcast live on national television. Andrew Lawson, a geologist from the University of California, Berkeley, had named the fault after the San Andreas Lake and later led an investigation into that event. The San Andreas Fault ruptured for a length of 290 mi during the 1906 shock, several long term forecasts for a large shock along the San Andreas Fault in that area had been made public prior to 1989 but the earthquake that transpired was not what had been anticipated. The 1989 Loma Prieta event originated on an undiscovered oblique-slip reverse fault that is located adjacent to the San Andreas Fault, since many forecasts had been presented for the region near Loma Prieta, seismologists were not taken by surprise by the October 1989 event. Two moderate shocks, referred to as the Lake Elsman earthquakes by the USGS, occurred in the Santa Cruz Mountains region in June 1988, each events aftershock sequence and effect on stress drop was closely examined, and their study indicated that the shocks affected the mainshocks rupture process. The June 27,1988, shock occurred with an intensity of VI. Its effects included broken windows in Los Gatos, and other damage in Holy City. Farther away from the Santa Cruz Mountains, pieces of concrete fell from a structure at the Sunnyvale Town Center. More moderate damage resulted from the August 8,1989, shock when chimneys were toppled in Cupertino, Los Gatos, other damage included cracked walls and foundations and broken underground pipes. At the office of the Los Gatos City Manager, a window that was cracked had also broken in the earlier shock. Also in Los Gatos, one man died when he exited a building through a window, the Loma Prieta earthquake was named for Loma Prieta Peak in the Santa Cruz Mountains, which lies just to the east of the mainshock epicenter. At sites with rocky terrain, the duration was shorter and the shaking was much less intense, the strong motion records also allowed for the causative fault to be determined – the rupture was related to the San Andreas Fault System. While a Mercalli Intensity of VIII covered a large swath of territory relatively close to the further to the north. At more than 44 miles distant, the San Francisco Bay Area recorded peak horizontal accelerations that were as high as 0. 26g, in a general way, the location of aftershocks of the event delineated the extent of the faulting, which extended about 24 miles in length. Because the rupture took place bilaterally, the duration of strong shaking was about half of what it would have been had it ruptured in one direction only, the duration of a typical M6.9 shock with a comparable rupture length would have been about twice as long. Gregory Beroza, a seismologist with Stanford University, made several distinctions regarding the 1906 and 1989 events, near Loma Prieta, the 1906 rupture was more shallow, had more strike-slip, and occurred on a fault that was near vertical
31.
Guinness World Records
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The book itself holds a world record, as the best-selling copyrighted book of all time. As of the 2017 edition, it is now in its 63rd year of publication, the international franchise has extended beyond print to include television series and museums. On 10 November 1951, Sir Hugh Beaver, then the director of the Guinness Breweries, went on a shooting party in the North Slob, by the River Slaney in County Wexford. After missing a shot at a golden plover, he involved in an argument over which was the fastest game bird in Europe. That evening at Castlebridge House, he realised that it was impossible to confirm in reference books whether or not the golden plover was Europes fastest game bird. Beaver knew that there must be numerous other questions debated nightly in pubs throughout Ireland and abroad and he realised then that a book supplying the answers to this sort of question might prove successful. Beavers idea became reality when Guinness employee Christopher Chataway recommended University friends Norris and Ross McWhirter, the twin brothers were commissioned to compile what became The Guinness Book of Records in August 1954. A thousand copies were printed and given away, after the founding of The Guinness Book of Records at 107 Fleet Street, the first 198-page edition was bound on 27 August 1955 and went to the top of the British best seller lists by Christmas. The following year, it launched in the US, and sold 70,000 copies, since then, Guinness World Records has become a household name and the global leader in world records. Because the book became a hit, many further editions were printed, eventually settling into a pattern of one revision a year, published in September/October. The McWhirters continued to compile it for many years, Ross McWhirter was assassinated by the Provisional Irish Republican Army in 1975. Following Ross assassination, the feature in the show where questions about records posed by children were answered was called Norris on the Spot, Guinness Superlatives Limited was formed in 1954 to publish the first book. Sterling Publishing owned the rights to the Guinness book in the US for decades, and, under their management, the group was owned by Guinness PLC and subsequently Diageo until 2001, when it was purchased by Gullane Entertainment. Gullane was itself purchased by HIT Entertainment in 2002, with offices in New York City and Tokyo, Guinness World Records global headquarters remain in London, while its museum attractions are based at Ripley headquarters in Orlando, Florida, US. Recent editions have focused on record feats by person competitors, many records also relate to the youngest person who achieved something, such as the youngest person to visit all nations of the world, being Maurizio Giuliano. Each edition contains a selection of the records from the Guinness database, as well as new records. The majority of records are no longer listed in the book or on the website. For those unable to wait the 4–6 weeks for a reply, the Guinness Book of Records is the worlds most sold copyrighted book, earning it an entry within its own pages
32.
Rincon Hill
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Rincon Hill is a neighborhood in San Francisco, California. It is one of San Franciscos 49 hills, and one of its original Seven Hills, the relatively compact neighborhood is bounded by Folsom Street to the north, the Embarcadero to the east, Bryant Street on the south, and Essex Street to the west. Rincon Hill is located just south of the Transbay development area, the hill is about 100 feet tall. Following the California Gold Rush, Rincon Hill was built up as a fashionable, after it was destroyed by the 1906 earthquake and fire, the neighborhood was slow to rebuild and largely became an industrial area with small factories and warehouses. In 1985, and revised in 2005, the area was rezoned into a high-density residential neighborhood designed to house up to 10,000 new residents in close proximity to the citys Financial District. The area comprising Rincon Hill was originally a peninsula forming the southern shoreline of Yerba Buena Cove. The peninsula terminated at Rincon Point, near Harrison and Spear streets, rincón is Spanish for corner, and the point formed the southern corner of the cove. Prior to the Gold Rush of 1849, the Rincon Hill area was largely unsettled, as most early development was on the side of the Cove. With the influx of gold seekers, the cove was filled in, Rincon Hills views and sunny climate made it attractive to families of merchants, sea captains, and other professional classes who sought refuge from the notorious Barbary Coast. During the 1850s and 1860s, the citys most prestigious residential neighborhoods were located south of Market Street on Rincon Hill and in the nearby neighborhood known as Happy Valley. The Second Street Cut of 1869, which sliced through Rincon Hill to reach areas to the south. A wealthy land owner and state assemblyman, John Middleton, proposed the leveling of Second Street through Rincon Hill to improve access to the southern waterfront, the 100-foot canyon split Rincon Hill in two and destabilized homes on either side of the Cut. With the advent of cars in the 1870s, the residential trend shifted towards new mansions built on the taller hills north of Market Street. In The Wrecker, Robert Louis Stevenson described Rincon Hill as a new slum, the 1906 earthquake and fire destroyed the remaining Rincon Hill mansions. In their place, a number of rudimentary earthquake shacks sprung up, while much of San Francisco was quickly rebuilt following the earthquake, Rincon Hill remained relatively undeveloped in the ensuing decades. Following the quake, the Marsden Manson report on reconstruction recommended that Rincon Hill be removed entirely to provide more flat ground close to the waterfront, although the plan was never enacted, it resurfaced in 1913 and 1927, discouraging real estate developers from building on the hill. The construction of the San Francisco–Oakland Bay Bridge in the 1930s cleared out the remaining shacks, ralston, William Gwin, H. H. Bancroft, and others. By the 1880s the hill, already partially leveled, became a working class district, today it is nearly invisible beneath the Bay Bridge
33.
Truss
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In engineering, a truss is a structure that consists of two-force members only, where the members are organized so that the assemblage as a whole behaves as a single object. A two-force member is a component where force is applied to only two points. In this typical context, external forces and reactions to those forces are considered to act only at the nodes and result in forces in the members that are either tensile or compressive. For straight members, moments are explicitly excluded because, and only because, all the joints in a truss are treated as revolutes, as is necessary for the links to be two-force members. A planar truss is one all members and nodes lie within a two dimensional plane, while a space truss has members and nodes that extend into three dimensions. The top beams in a truss are called top chords and are typically in compression, the beams are called bottom chords. The interior beams are called webs, and the areas inside the webs are called panels, Truss derives from the Old French word trousse, from around 1200, which means collection of things bound together. The term truss has often used to describe any assembly of members such as a cruck frame or a couple of rafters. One engineering definition is, A truss is a single plane framework of individual structural member connected at their ends of forms a series of triangle to span a large distance, a truss consists of typically straight members connected at joints, traditionally termed panel points. Trusses are typically composed of triangles because of the stability of that shape. A triangle is the simplest geometric figure that will not change shape when the lengths of the sides are fixed, in comparison, both the angles and the lengths of a four-sided figure must be fixed for it to retain its shape. The joint at which a truss is designed to be supported is commonly referred to as the Munter Point, the simplest form of a truss is one single triangle. This type of truss is seen in a roof consisting of rafters and a ceiling joist. Because of the stability of this shape and the methods of used to calculate the forces within it. The traditional diamond-shape bicycle frame, which utilizes two conjoined triangles, is an example of a simple truss, a planar truss lies in a single plane. Planar trusses are used in parallel to form roofs and bridges. The depth of a truss, or the height between the upper and lower chords, is what makes it an efficient structural form, a solid girder or beam of equal strength would have substantial weight and material cost as compared to a truss. For a given span, a deeper truss will require less material in the chords, an optimum depth of the truss will maximize the efficiency
34.
Causeway
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In modern usage, a causeway is a road or railway on top an embankment usually across a broad body of water or wetland. When first used, the word appeared in a such as causey way making clear its derivation from the earlier form causey. This word seems to have come from the source by two different routes. It derives ultimately, from the Latin for heel, calx, anciently, the construction was trodden down, one layer at a time, often by slaves or flocks of sheep. Today, this work is done by machines, the same technique would have been used for road embankments, raised river banks, sea banks and fortification earthworks. The second derivation route is simply the hard, trodden surface of a path, the name by this route came to be applied to a firmly-surfaced road. It is now little-used except in dialect and in the names of roads which were notable for their solidly-made surface. The 1911 Encyclopædia Britannica states causey, a mound or dam, which is derived, through the Norman-French caucie, from the late Latin via calciata, a road stamped firm with the feet. The word is comparable in both meanings with the French chaussée, from a form of which it reached English by way of Norman French. The French adjective, chaussée, carries the meaning of having given a hardened surface. As a noun chaussée is used on the one hand for a metalled carriageway, other languages have a noun with similar dual meaning. The Welsh is relevant here, as it also has a verb, sarnu, a transport corridor that is carried instead on a series of arches, perhaps approaching a bridge, is a viaduct. In the U. S. a short stretch of viaduct is called an overpass, some low causeways across shore waters become inaccessible when covered at high tide. The modern embankment may be constructed within a cofferdam, two parallel steel sheet pile or concrete retaining walls, anchored to each other with steel cables or rods. This construction may also serve as a dyke that keeps two bodies of water apart, such as bodies with a different water level on each side, or with water on one side. This may also be the purpose of a structure, the road providing a hardened crest for the dike. It also provides access for maintenance as well perhaps, as a public service, notable causeways include those that connect Singapore and Malaysia, Bahrain and Saudi Arabia and Venice to the mainland, all of which carry roadways and railways. In the Netherlands there are a number of prominent dykes which also double as causeways, including the Afsluitdijk, Brouwersdam, in Louisiana, two very long bridges, called the Lake Pontchartrain Causeway, stretch across Lake Pontchartrain for almost 38 km, making them the worlds longest bridges
35.
Viaduct
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A viaduct is a bridge composed of several small spans for crossing a valley, dry or wetland, or forming a flyover. The term viaduct is derived from the Latin via for road and ducere, the ancient Romans did not use the term, it is a modern derivation from an analogy with aqueduct. Like the Roman aqueducts, many early viaducts comprised a series of arches of equal length. Viaducts may span land, water or both, a viaduct is a bridge composed of several small spans for crossing a valley or a gorge. The term is conventional for a flyover as opposed to a flying junction or a rail bridge which crosses one feature. In Romance languages, the word refers to a bridge which spans only land. A bridge spanning water is called ponte, the longest viaduct in antiquity may have been the Pont Serme which crossed wide marshes in southern France. Viaducts are commonly used in cities that are railroad centers, such as Chicago, Atlanta, Birmingham, London. These viaducts cross the railroad yards that are needed for freight trains there. These viaducts keep highway and city street traffic from having to be interrupted by the train traffic. Likewise, some viaducts carry railroads over large valleys, or they carry railroads over cities with many cross-streets, many viaducts over land connect points of similar height in a landscape, usually by bridging a river valley or other eroded opening in an otherwise flat area. Often such valleys had roads descending either side that become inadequate for the traffic load, such bridges also lend themselves for use by rail traffic, which requires straighter and flatter routes. Some viaducts have more than one deck, such that one deck has vehicular traffic, others were built to span settled areas, crossing over roads beneath—the reason for many viaducts in London. Viaducts over water use of islands or successive arches. The Millau Viaduct is a cable-stayed road-bridge that spans the valley of the River Tarn near Millau in southern France and it was formally dedicated on 14 December 2004 and opened to traffic two days later. The viaduct Danyang–Kunshan Grand Bridge in China is the longest bridge in the according to Guinness World Records as of 2011. Where a viaduct is built across land rather than water, the space below the arches may be used for such as car parking, vehicle repairs, light industry, bars. In the United Kingdom, many lines in urban areas have been constructed on viaducts
36.
FasTrak
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FasTrak is the electronic toll collection system used in the state of California in the United States. The system is used statewide on all of the roads, toll bridges. As with other ETC systems, FasTrak is designed to eliminate the need for cars to stop to pay at toll booths and its use of technology to improve transit is in line with the U. S. Department of Transportations Intelligent Transportation Systems initiative. Under Californias government structure, the states toll facilities are operated by various agencies, three years later, Transportation Corridor Agencies opened the Foothill Toll Road in Orange County, implementing the statewide ETC system for the first time, and naming it FasTrak. The state continues to delegate the responsibility of selling and maintaining FasTrak accounts to the different toll agencies, under California law, the California Department of Transportation was given the mandate to develop and maintain an open, statewide ETC specification. This specification is known in the industry as Title 21 after it was added to Title 21 of the California Code of Regulations. FasTrak uses RFID technology near 915 MHz to read data from a placed in a vehicle moving at speeds that may exceed 70 mph. The RFID transponder in each vehicle is associated with a debit account, each time the vehicle passes underneath a toll collection site. Currently, FasTrak transponders are not compatible with E-ZPass and other ETC systems used in other states because they use a different specification than Title 21. If the license plate is registered as belonging to a FasTrak user, the account is debited only the toll charge and this is a backup in case a transponder fails to read. Otherwise, a violation notice is sent to the registered owner of the vehicle. A license plate may be listed only on one account, a toll collected based on a license plate is called an Image Toll and can be identified on the customer statement by noticing the license plate number listed instead of the transponder number. If one fails to correctly list license plates on their account, conversely, a license plate should be removed from an account after a change in ownership. Failure to do so may result in paying for another drivers tolls via the Image Toll process, each toll agency in Southern California has their own billing and customer service center. For convenience, all facilities in the San Francisco Bay Area instead share the same billing. Each center establishes its own fee and discount structures, and people may be charged a fee if the majority of their FasTrak use occurs elsewhere, a teardown analysis of the transponder and analysis of its security issues was published at Black Hat 2008. They are updated remotely, and do not use encryption, FasTrak units are used to generate 5-1-1 traffic data, using sensors and antennae placed across various freeways. As the first ETC system in North America was installed on the Dallas North Tollway in 1989, as a result, California was the first in the nation to require all of its toll bridges and roads to use the same ETC system
37.
Ramp meter
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It is the use of traffic signals at freeway on-ramps to manage the rate of automobiles entering the freeway. Ramp metering systems have proved to be successful in decreasing traffic congestion, Ramp meters are claimed to reduce congestion on freeways by reducing demand and by breaking up platoons of cars. Two variations of demand reduction are commonly cited, one being access rate, other ramp meters are designed to operate continuously, only being turned off for maintenance or repairs. Some metered ramps have bypass lanes for vehicles, allowing carpoolers and buses to skip the queue. In other places such as Northern California, carpool lanes are still metered, Meters often only operate in rush hour periods. Some ramp meters have only one lane of traffic at the signal, generally, meters with multiple lanes only give one lane the green light at a time. In one common configuration, each entrance lane has two signals, a red-yellow-green signal perched overhead over each lane, and a lamp mounted low on a pole next to the stop line. The overhead lights are for cars approaching the point, the low-mounted two-phase lights are intended to be used by the vehicle at the front of the queue. In normal operation of the meters, only the red. However, when ramp metering is about to be enabled, the lamps may show flashing or solid yellow to warn drivers to prepare to stop. In California, some meters allow two or three cars to proceed on a green light and these meters use red-yellow-green signals on both the upper and lower mounts on the pole, and operate in a standard green-yellow-red fashion. In Ontario, the ramp meter lights are green when there are no restrictions in place for traffic to proceed. The simplest form of control is a fixed time operation and it performs the basic functions of breaking up platoons into single-vehicle entries and setting an upper limit on the flow rates that enter the freeway. This type of operation provides the benefits associated with accident reductions, pre-timed control can be implemented on any number of ramps, and is often implemented as an initial operating strategy until individual ramps can be incorporated into a traffic responsive system. The next level of control, traffic responsive, establishes metering rates based on actual freeway conditions, system-wide control is a form of traffic responsive control but operates on the basis of total freeway conditions. Centralized computer controlled systems can handle numerous ramps in a traffic responsive scheme and feature multiple control programs, control strategies can also be distributed among individual ramps. A significant feature of system control is interconnection that permits the metering rate at any ramp to be influenced by conditions at other locations. Denver showed that type of control has significant benefits when properly applied. ’ System control need not be limited to the freeway
38.
High-occupancy vehicle lane
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The normal minimum occupancy level is 2 or 3 occupants. Regional and corporate-sponsored vanpools, carpools, and rideshare communities give commuters a way to increase occupancy, for places without such services, online rideshare communities can serve a similar purpose. Slugging lines are common in places, where solo drivers pick up a passenger to share the ride. High-occupancy toll lanes have been introduced in the United States to allow solo driver vehicles to use the lane on payment of a variable fee, the introduction of HOV lanes in the United States progressed slowly during the 1970s and early 1980s. Major growth occurred from the mid-1980s to the late 1990s, the busway was opened in December 1973 to carpools with four or more occupants, becoming the first instance in which buses and carpools officially shared a HOV lane over a considerable distance. Average travel time in the HOV facility was 29 minutes, and 64 minutes in the traffic lanes. Three or more people in a vehicle are required to travel on the facility during rush hours on weekdays, the second freeway HOV facility was the contraflow bus lane on the Lincoln Tunnel Approach and Helix in Hudson County, New Jersey, opened in 1970. The first permanent HOV facility in California was the lane at the San Francisco–Oakland Bay Bridge toll plaza. The El Monte Busway in Los Angeles was initially available for buses when it opened in 1973. Three-person carpools were allowed to use the bus lane for three months in 1974 due to a strike by bus operators, and then permanently at a 3+ HOV from 1976. Beginning in the 1970s, the Urban Mass Transit Administration recognized the advantages of exclusive bus lanes, in the 1970s the FHWA began to allow state highway agencies to spend federal funds on HOV lanes. As a result of the 1973 Arab Oil Embargo, interest in ridesharing picked up, the 1978 Surface Transportation Assistance Act made funding for rideshare initiatives permanent. Also during the early 1970s, ridesharing was recommended for the first time as a tool to mitigate air quality problems, the 1970 Clean Air Act Amendments established the National Ambient Air Quality Standards and gave the Environmental Protection Agency substantial authority to regulate air quality attainment. However, it took until 1985 before any HOV project was constructed in Los Angeles County, regional administrators were directed to promote HOV lanes and related facilities. Also in the early 1990s, two laws reinforced the U. S. commitment to HOV lane construction, the Clean Air Act Amendments of 1990 included HOV lanes as one of the transportation control measures that could be included in state implementation plans to attain federal air quality standards. CMAQ funds may be spent on new HOV lane construction, even if the HOV designation holds only at peak times or in the peak direction. ISTEA also provided that under the Interstate Maintenance Program, only HOV projects would receive the 90% federal matching ratio formerly available for the addition of general purpose lanes, and ISTEA permitted state authorities to define a high occupancy vehicle as having a minimum of two occupants. As of 2009, California was the state with the most HOV facilities in the country, with 88, followed by Minnesota with 83 facilities, Washington with 41, Texas with 35, and Virginia with 21
39.
Median strip
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The median strip or central reservation is the reserved area that separates opposing lanes of traffic on divided roadways, such as divided highways, dual carriageways, freeways, and motorways. The term also applies to divided roadways other than highways, such as major streets in urban or suburban areas. There is no international English standard for the term, median, median strip, and median divider island are common in North American and Antipodean English. Variants in North American English include regional terms such as neutral ground in New Orleans usage, among other coinages, central nature strip occurs in Australian English. Additionally, different terminology is used to traffic lanes in a multi-lane roadway. North American usage calls the lanes located closest to the roadway centerline the inner lanes, thus, it is less confusing to call these central lanes the passing, fast, or overtaking lanes in international contexts, instead of using the ambiguous inner/outer distinction. Regional differences between right-hand traffic and left-hand traffic can cause further confusion, some medians function secondarily as green areas and green belts to beautify roadways. Where space is at a premium, dense hedges of shrubs filter the headlights of oncoming traffic, in contrast to the median of a major road, those in urban areas often take the form of central traffic islands that rise above the roadway. These are frequently found on urban arterial roads, in their simplest form, these are just raised concrete curbs, but can also be landscaped with grass or trees or decorated with bricks or stones. In some areas, such as California, highway medians are sometimes no more than a section of the paved roadway. The medians of United States Interstate Highways break only for emergency service lanes, on British motorways, the median is never broken, but there are no such restrictions on other dual carriageways. The median strip in the United Kingdom and other densely populated European countries is no wider than a single lane of traffic. In some cases, however, it is extended, for instance, if the road is running through hilly terrain, the carriageways may have to be built on different levels of the slope. An example of this is on the M5 motorway as it climbs up the side of the Gordano Valley south of Bristol. The other major exception is the A38 Aston Expressway, which is a carriageway of seven lanes. All existing motorways will introduce concrete barriers as part of ongoing upgrades and through replacement as and this change of policy applies only to barriers in the median of high speed roads and not to verge side barriers. Other routes will continue to use steel barriers, in urban areas, concrete barriers and guard rails are used. In Dedham, Massachusetts, the Norfolk County Correctional Center is located entirely within a median of Massachusetts Route 128
40.
Traffic congestion
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Traffic congestion is a condition on transport networks that occurs as use increases, and is characterized by slower speeds, longer trip times, and increased vehicular queueing. The most common example is the use of roads by vehicles. When traffic demand is great enough that the interaction between vehicles slows the speed of the stream, this results in some congestion. As demand approaches the capacity of a road, extreme traffic congestion sets in, when vehicles are fully stopped for periods of time, this is colloquially known as a traffic jam or traffic snarl-up. Traffic congestion can lead to becoming frustrated and engaging in road rage. Mathematically, congestion is usually looked at as the number of vehicles that pass through a point in a window of time, Congestion flow lends itself to principles of fluid dynamics. Traffic congestion occurs when a volume of traffic or modal split generates demand for greater than the available street capacity. About half of U. S. traffic congestion is recurring, Traffic research still cannot fully predict under which conditions a traffic jam may suddenly occur. It has been found that individual incidents may cause ripple effects which then spread out and create a traffic jam when, otherwise. Some traffic engineers have attempted to apply the rules of fluid dynamics to traffic flow, Traffic scientists liken such a situation to the sudden freezing of supercooled fluid. However, unlike a fluid, traffic flow is affected by signals or other events at junctions that periodically affect the smooth flow of traffic. Alternative mathematical theories exist, such as Boris Kerners three-phase traffic theory, because of the poor correlation of theoretical models to actual observed traffic flows, transportation planners and highway engineers attempt to forecast traffic flow using empirical models. These models are typically calibrated by measuring actual traffic flows on the links in the network. That discovery enabled the team to solve traffic-jam equations that were first theorized in the 1950s, congested roads can be seen as an example of the tragedy of the commons. Privatization of highways and road pricing have both proposed as measures that may reduce congestion through economic incentives and disincentives. Congestion can also happen due to non-recurring highway incidents, such as a crash or roadworks, economist Anthony Downs argues that rush hour traffic congestion is inevitable because of the benefits of having a relatively standard work day. In a capitalist economy, goods can be allocated either by pricing or by queueing and they determined that the number of vehicle-kilometers traveled increases in direct proportion to the available lane-kilometers of roadways. The implication is that new roads and widening existing ones only results in additional traffic that continues to rise until peak congestion returns to the previous level
41.
MacArthur Maze
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The MacArthur Maze is a large freeway interchange near the east end of the San Francisco–Oakland Bay Bridge in Oakland, California. It splits Bay Bridge traffic into three freeways—the Eastshore, MacArthur and Nimitz and it is also next to the Port of Oakland, the fourth busiest container port in the United States. The four freeways intersecting at this interchange are, I-80 west – San Francisco Interstate 80 from the Maze heads west across the Bay Bridge into San Francisco, where it joins US101. I-80 east / I-580 west – Berkeley, Sacramento, San Rafael The Interstate 80/Interstate 580 concurrency from the Maze heads north through Berkeley, just north of the Berkeley-Albany border, approximately 4 miles north of the Maze, the concurrency splits. Interstate 80 heads northeast towards Sacramento, Interstate 580 heads northwest towards the Richmond-San Rafael Bridge and eventually to Marin County, where it joins U. S.101 in San Rafael. I-580 east to SR24 / I-980 – Downtown Oakland, Walnut Creek, Hayward, a mile southeast is an interchange with State Route 24/Interstate 980, a corridor for commuters from Contra Costa County. I-580 continues southeast along the foot of the hills to Castro Valley, I-580 then turns east and continues through the Livermore Valley, over Altamont Pass, and ending up near Tracy where it terminates at Interstate 5. Local traffic using the interchange includes East Bay commuters to and from San Francisco via the Bay Bridge, as well as drivers traveling up, for long distance traffic accessing other parts of the country, I-80 is the primary Interstate Highway for points east. Furthermore, drivers on US101 who want to bypass San Francisco can use I-880 from San Jose to the Maze, the Maze started as part of the construction of the Bay Bridge in the 1930s. It was named the Distribution Structure but eventually became the Maze to the media, a parallel set of ramps handled eastward/southward traffic. The original 1936 ramps were removed during this 1990s construction, film footage of the early Maze can be seen in the 1941 movie Shadow of the Thin Man, as Nick and Nora Charles drive off the Bay Bridge on their way to Golden Gate Fields in Albany. During the 6.9 Mw Loma Prieta earthquake, the double-decked Cypress Street Viaduct on I-880 between I-80 and the 14th Street exit collapsed, crushing cars and killing 42 people. The Cypress Street Viaduct was demolished soon after the earthquake, but a replacement freeway wasnt finished until July 1997, due to lawsuits by environmentalists, the final connection to the Maze, known as the East Bay Viaduct, opened in 1998. The replacement sections of the Nimitz Freeway dispensed with the double-deck design and it was built near the Union Pacific railway tracks around the outskirts of West Oakland, rather than bisecting that neighborhood as the Cypress Viaduct had. Cypress Street, which ran on each side of the old highway, is now a landscaped parkway and has been renamed Mandela Parkway. In 2007 Mandela Parkway was linked at its end with the west end of Yerba Buena Avenue. At 3,42 am on Sunday, April 29,2007, no other vehicles or persons were reported to be involved in the accident. The California Highway Patrol initially reported that they suspected that the tanker had been speeding and bounced off a guard rail, the driver was found to have a clean record the preceding decade, drug or alcohol use was determined not to be a factor in the accident
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Interstate 580 (California)
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Interstate 580 is an 80-mile east–west Interstate Highway in Northern California. The heavily traveled spur route of Interstate 80 runs from San Rafael in the San Francisco Bay Area to Interstate 5 near Tracy in the Central Valley. It provides a connection from the Bay Area to the southern San Joaquin Valley and Southern California via Interstate 5, a portion of I-580 is called the MacArthur Freeway, after General Douglas MacArthur. Other portions are named the John T. Knox Freeway, the Eastshore Freeway, the Arthur H. Breed Jr. Freeway, the William Elton Brownie Brown Freeway, daniel Sakai Memorial Highway, and the John P. Miller Memorial Highway. This route is part of the California Freeway and Expressway System and is eligible for the State Scenic Highway System, the western terminus of I-580 is roughly 10 miles north of San Francisco in the city of San Rafael, at the junction with U. S. Route 101. The interchange with US101 is incomplete, only allowing continuous travel from southbound US101 to eastbound I-580, I-580 enters the city of Richmond in Contra Costa County mid-span, then continues through Richmond to join Interstate 80 in Albany at the Hoffman Split. After joining I-80, I-580 runs directly south for several miles along the shore of San Francisco Bay in the segment known as the Eastshore Freeway. The segment between the Hoffman Split and the MacArthur Maze is a concurrency, meaning I-580 east is signed as I-80 west. From the MacArthur Maze, I-580 is known as the MacArthur Freeway, about halfway to Castro Valley from the Maze, is an interchange with the Warren Freeway. Between this interchange and Castro Valley, I-580 runs near or along the trace of the Hayward Fault, in Castro Valley, I-580 turns eastward toward Dublin Canyon before descending into Dublin and Pleasanton. After passing through Livermore, the freeway enters the Altamont Pass, I-580 provides Interstate Highway access between San Francisco and Los Angeles since I-5 runs east of the Bay Area. However, the control city listed on freeway signs along eastbound I-580 between I-80 and I-205 is instead Stockton, a vestige of when this segment used to be part of US50. Trucks over 4.5 tons are prohibited through Oakland between Grand Avenue and the San Leandro border, specifically, eastbound trucks cannot travel beyond Grand Avenue/Lakeshore Avenue, and those going westbound must get off at MacArthur Boulevard/Foothill Boulevard. They are instead instructed to take I-238 in Castro Valley and then I-880 through Oakland as an alternative route, the truck prohibition has been in effect since the freeway was built in 1963 as part of US50. Since then, the restriction was grandfathered in when the freeway was renumbered and added to the Interstate Highway System. As a result, it is the segment of Interstate Highway in California that is not part of the National Truck Network. With trucks normally rerouted onto I-880 instead of I-580 through Oakland, for decades, the trucking industry lobbied to have the ban removed, but was unsuccessful due to local opposition. In 2000, the California State Legislature passed Assembly Bill 500, the ban is temporarily lifted by the California Highway Patrol for short periods to reduce traffic congestion when major accidents occur on I-880 or I-238
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Interstate 880
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Interstate 880 is an Interstate Highway in the San Francisco Bay Area connecting San Jose and Oakland, running parallel to the northeastern shore of San Francisco Bay. For most of its route, I-880 is officially known as the Nimitz Freeway, after World War II fleet admiral Chester Nimitz and this route is part of the California Freeway and Expressway System. The southern terminus of I-880 is at its interchange with Interstate 280, from there, it heads roughly northeast past the San Jose International Airport to U. S. Route 101. In Oakland, I-880 passes by Oakland International Airport, Oakland-Alameda County Coliseum, the northern terminus of I-880 is in Oakland at the junction with Interstate 80 and Interstate 580, near the eastern approach of the Bay Bridge. I-880 between I-238 in San Leandro and the MacArthur Maze is used as a truck route. Officially, the Nimitz Freeway designation is Route 880 from Route 101 to Route 80, as named by Senate Concurrent Resolution 23 and it then turned north at Cypress Street, passing through the Bay Bridge Distribution Structure and following a newly constructed alignment to El Cerrito. The first short piece of the new Eastshore Freeway opened to traffic on July 22,1949 and it was extended to 98th Avenue on June 1,1950, Lewelling Boulevard on June 13,1952, and Jackson Street on June 5,1953. At the San Jose end, the overlap with Route 5 between Bayshore Highway and Warm Springs was bypassed on July 2,1954, within Oakland, the double-decker Cypress Street Viaduct opened on June 11,1957, connecting the freeway with the San Francisco–Oakland Bay Bridge. As these sections opened, Sign Route 17 was moved from its old surface routing, other than Route 5 south of Warm Springs, the portion from San Leandro into Oakland was also kept as part of Route 105. Prior to 1984, the known as I-880 used to be part of State Route 17. SR17 used to run from Santa Cruz all the way through San Jose, Oakland, in 1947, construction commenced on a freeway to replace the street routing of SR17 through the East Bay. In 1958, the south of the MacArthur Maze was renamed the Nimitz Freeway in honor of WWII Admiral Nimitz. The northern portion of I-880 was designated Business U. S. Route 50 for a time between the I-80 interchange and downtown Oakland, from 1971 to 1983, Interstate 880 was the original route designation for the Beltline Freeway, the northern bypass freeway for the Sacramento area. The now-designated Capital City Freeway was then the original I-80 routing, continuing southwest directly into downtown Sacramento, I-80 was then re-routed along the Beltline Freeway in 1983, while the Capital City Freeway became Interstate 80 Business. This was the greatest loss of life caused by that earthquake, the freeway reopened in July 1997 on a new route parallel to railroad tracks around the outskirts of West Oakland with the entire project being completed shortly before 2000. Although only about three miles in length, the replacement freeway cost over $1, the former path of the structure, Cypress Street, was renamed Mandela Parkway, and the median where the freeway stood became a landscaped linear park. Several aspects of the I-880 facility have been constructed in designated floodplains such as the 1990 interchange improvements at Dixon Landing Road, in that case the Federal Highway Administration was required to make a finding that there was no feasible alternative to the new ramp system as designed. In that same study, the FHWA produced an analysis to support the fact that adequate wetlands mitigation had been designed into the improvement project and this activity has occurred in Oakland, San Leandro, Hayward, Newark and Fremont
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Richmond, California
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Richmond is a city in western Contra Costa County, California, United States. The city was incorporated on August 7,1905, under the McLaughlin Administration, Richmond was the largest city in the United States served by a Green Party mayor. As of the 2010 U. S. Census, the population is at 103,710. The largest, Richmond, Virginia, is the namesake of the California city, the Ohlone Indians were the first inhabitants of the Richmond area, settling an estimated 5,000 years ago. The name Richmond appears to predate actual incorporation by more than fifty years, the Atchison, Topeka and Santa Fe Railroad had its terminus at Richmond. The first post office opened in 1900, Richmond was founded and incorporated in 1905, carved out of Rancho San Pablo, from which the nearby town of San Pablo inherited its name. Until the enactment of prohibition in 1919, the city had the largest winery in the world, in the 1920s the Ku Klux Klan was active in the city. In 1930 the Ford Motor Company opened a plant called Richmond Assembly Plant which moved to Milpitas in the 1960s. The old Ford plant has been a National Historic Place since 1988, the city was a small town at that time, until the onset of World War II which brought on a rush of migrants and a boom in the industrial sector. Standard Oil set up here in 1901, including a what is now the Chevron Richmond Refinery and tank farm. There is a pier into San Francisco Bay south of Point Molate for oil tankers, the western terminus of the Santa Fe Railroad was established in Richmond with ferry connections at Ferry Point in the Brickyard Cove area of Point Richmond to San Francisco. Many of these lived in specially constructed houses scattered throughout the San Francisco Bay Area, including Richmond, Berkeley. A specially built rail line, the Shipyard Railway, transported workers to the shipyards, kaisers Richmond shipyards built 747 Victory and Liberty ships for the war effort, more than any other site in the U. S. The city broke many records and even built one Liberty ship in a five days. On average the yards could build a ship in thirty days, the medical system established for the shipyard workers at the Richmond Field Hospital eventually became todays Kaiser Permanente HMO. It remained in operation until 1993 when it was replaced by the modern Richmond Medical Center hospital, Point Richmond was originally the commercial hub of the city, but a new downtown arose in the center of the city. It was populated by many department stores such as Kress, J. C. Penney, Sears, Macys, during the war the population increased dramatically and peaked at around 120,000 by the end of the war. Once the war ended the workers were no longer needed
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Freeway
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A controlled-access highway is a type of highway which has been designed for high-speed vehicular traffic, with all traffic flow and ingress/egress regulated. Common English terms are freeway, motorway and expressway, other similar terms include Interstate and parkway. Some of which may be limited-access highways, although this term can refer to a class of highway with somewhat less isolation from other traffic. In countries following Vienna convention, the motorway qualification implies they are forbidden for walking or parking, a controlled-access highway provides an unhindered flow of traffic, with no traffic signals, intersections or property access. They are free of any at-grade crossings with roads, railways, or pedestrian paths. Entrances and exits to the highway are provided at interchanges by slip roads, on the controlled-access highway, opposing directions of travel are generally separated by a median strip or central reservation containing a traffic barrier or grass. Elimination of conflicts with other directions of traffic dramatically improves safety and capacity, controlled-access highways evolved during the first half of the 20th century. Italy opened its first autostrada in 1924 connecting Milan to Varese, Germany began to build its first 30-kilometre autobahn controlled-access highway without speed limits in 1932 between Cologne and Bonn. It then rapidly constructed a system of such roads in anticipation of their use in the Second World War. The first North American freeways opened in the New York City area in the 1920s, Britain, heavily influenced by the railways, did not build its first motorway, the Preston By-pass, until 1958. Most technologically advanced nations feature a network of freeways or motorways to provide high-capacity urban travel, or high-speed rural travel. Many have a national-level or even international-level system of route numbering, exit is marked with another symbol. The definitions of motorway from the OECD and PIARC are almost identical, british Standards Motorway, Limited-access dual carriageway road, not crossed on the same level by other traffic lanes, for the exclusive use of certain classes of motor vehicle. ITE Freeway, A divided major roadway with full control of access and this definition applies to toll as well as toll-free roads. Freeway A, This designates roadways with greater complexity and high traffic volumes. Usually this type of freeway will be found in areas in or near the central core. Freeway B, This designates all other divided roadways with full control of access where lighting is needed, principal arterials may cross through urban areas, serving suburban movements. The traffic is characterized by high speeds and full or partial access control, other roads leading to a principal arterial are connected to it through side collector roads
I-80 throughout, and pedestrians and bicycles east of Yerba Buena Island (YBI)
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