Tar
Tar is a black mixture of hydrocarbons and free carbon obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, petroleum, or peat and trade in pine-derived tar was a major contributor in the economies of Northern Europe and Colonial America. Its main use was in preserving wooden vessels against rot, the largest user was the Royal Navy. Demand for tar declined with the advent of iron and steel ships, tar-like products can be produced from other forms of organic matter, such as peat. Mineral products resembling tar can be produced from hydrocarbons, such as petroleum. Coal tar is produced from coal as a byproduct of coke production, Bitumen is a term used for natural deposits of oil tar, such as at the La Brea Tar Pits. In Northern Europe, the word tar refers primarily to a substance that is derived from the wood, in earlier times it was often used as a water repellent coating for boats and roofs. It is still used as an additive in the flavoring of candy, producing tar from wood was known in ancient Greece and has probably been used in Scandinavia since the Iron Age.
For centuries, dating back at least to the 14th century, sweden exported 13,000 barrels of tar in 1615 and 227,000 barrels in the peak year of 1863. Production nearly stopped in the early 20th century, when other chemicals replaced tar, traditional wooden boats are still sometimes tarred. The heating of wood causes tar and pitch to drip away from the wood. Birch bark is used to make particularly fine tar, known as Russian oil, the by-products of wood tar are turpentine and charcoal. When deciduous tree woods are subjected to distillation, the products are methanol. Tar kilns are dry distillation ovens, historically used in Scandinavia for producing tar from wood and they were built close to the forest, from limestone or from more primitive holes in the ground. The bottom is sloped into a hole to allow the tar to pour out. The wood is split into dimensions of a finger, stacked densely, if oxygen can enter, the wood might catch fire, and the production would be ruined. On top of this, a fire is stacked and lit, after a few hours, the tar starts to pour out and continues to do so for a few days.
Tar was used as seal for roofing shingles and tar paper and to seal the hulls of ships, for millennia, wood tar was used to waterproof sails and boats, but today, sails made from inherently waterproof synthetic substances have reduced the demand for tar
Ice age
An ice age is a period of long-term reduction in the temperature of Earths surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Within a long-term ice age, individual pulses of cold climate are termed glacial periods, in the terminology of glaciology, ice age implies the presence of extensive ice sheets in both northern and southern hemispheres. In 1742 Pierre Martel, an engineer and geographer living in Geneva, two years he published an account of his journey. He reported that the inhabitants of that valley attributed the dispersal of erratic boulders to the glaciers, similar explanations were reported from other regions of the Alps. In 1815 the carpenter and chamois hunter Jean-Pierre Perraudin explained erratic boulders in the Val de Bagnes in the Swiss canton of Valais as being due to glaciers previously extending further. An unknown woodcutter from Meiringen in the Bernese Oberland advocated a similar idea in a discussion with the Swiss-German geologist Jean de Charpentier in 1834, comparable explanations are known from the Val de Ferret in the Valais and the Seeland in western Switzerland and in Goethes scientific work.
Such explanations could be found in parts of the world. When the Bavarian naturalist Ernst von Bibra visited the Chilean Andes in 1849–1850, European scholars had begun to wonder what had caused the dispersal of erratic material. From the middle of the 18th century, some discussed ice as a means of transport, the Swedish mining expert Daniel Tilas was, in 1742, the first person to suggest drifting sea ice in order to explain the presence of erratic boulders in the Scandinavian and Baltic regions. In 1795, the Scottish philosopher and gentleman naturalist, James Hutton, two decades later, in 1818, the Swedish botanist Göran Wahlenberg published his theory of a glaciation of the Scandinavian peninsula. He regarded glaciation as a regional phenomenon, only a few years later, the Danish-Norwegian geologist Jens Esmark argued a sequence of worldwide ice ages. In a paper published in 1824, Esmark proposed changes in climate as the cause of those glaciations and he attempted to show that they originated from changes in Earths orbit.
During the following years, Esmarks ideas were discussed and taken over in parts by Swedish, Scottish, at the University of Edinburgh Robert Jameson seemed to be relatively open to Esmarks ideas, as reviewed by Norwegian professor of glaciology Bjørn G. Andersen. Jamesons remarks about ancient glaciers in Scotland were most probably prompted by Esmark, in Germany, Albrecht Reinhard Bernhardi, a geologist and professor of forestry at an academy in Dreissigacker, since incorporated in the southern Thuringian city of Meiningen, adopted Esmarks theory. In a paper published in 1832, Bernhardi speculated about former polar ice caps reaching as far as the zones of the globe. When he read his paper before the Schweizerische Naturforschende Gesellschaft, most scientists remained sceptical, Venetz convinced his friend Jean de Charpentier. De Charpentier transformed Venetzs idea into a theory with a limited to the Alps. In fact, both men shared the same volcanistic, or in de Charpentiers case rather plutonistic assumptions, about the Earths history, in 1834, de Charpentier presented his paper before the Schweizerische Naturforschende Gesellschaft
Traffic
Traffic on roads may consist of pedestrians, ridden or herded animals, streetcars and other conveyances, either singly or together, while using the public way for purposes of travel. Organized traffic generally has well-established priorities, right-of-way, Traffic is formally organized in many jurisdictions, with marked lanes, intersections, traffic signals, or signs. Traffic is often classified by type, heavy vehicle, other vehicle. Different classes may share speed limits and easement, or may be segregated, some jurisdictions may have very detailed and complex rules of the road while others rely more on drivers common sense and willingness to cooperate. Organization typically produces a combination of travel safety and efficiency. Events which disrupt the flow and may cause traffic to degenerate into a disorganized mess include road construction, collisions, on particularly busy freeways, a minor disruption may persist in a phenomenon known as traffic waves. A complete breakdown of organization may result in traffic congestion and gridlock, simulations of organized traffic frequently involve queuing theory, stochastic processes and equations of mathematical physics applied to traffic flow.
The word traffic originally meant trade and comes from the Old Italian verb trafficare, the origin of the Italian words is unclear. Rules of the road and driving etiquette are the practices and procedures that road users are required to follow. These rules usually apply to all users, though they are of special importance to motorists and cyclists. These rules govern interactions between vehicles and with pedestrians, the basic traffic rules are defined by an international treaty under the authority of the United Nations, the 1968 Vienna Convention on Road Traffic. Not all countries are signatory to the convention and, even among signatories, there are unwritten local rules of the road, which are generally understood by local drivers. These rules should be distinguished from the procedures required to operate ones vehicle. Traffic going in opposite directions should be separated in such a way that they do not block each others way, the most basic rule is whether to use the left or right side of the road.
In many countries, the rules of the road are codified, in the United Kingdom, the rules are set out in the Highway Code, which includes obligations but advice on how to drive sensibly and safely. In the United States, traffic laws are regulated by the states and municipalities through their respective traffic codes, most of these are based at least in part on the Uniform Vehicle Code, but there are variations from state to state. However, states such as South Carolina have completely criminalized their traffic law, so, for example, vehicles often come into conflict with other vehicles and pedestrians because their intended courses of travel intersect, and thus interfere with each others routes. The general principle that establishes who has the right to go first is called right of way and it establishes who has the right to use the conflicting part of the road and who has to wait until the other does so
Cone penetration test
The cone penetration or cone penetrometer test is a method used to determine the geotechnical engineering properties of soils and delineating soil stratigraphy. It was initially developed in the 1950s at the Dutch Laboratory for Soil Mechanics in Delft to investigate soft soils, based on this history it has been called the Dutch cone test. Today, the CPT is one of the most used and accepted methods for soil investigation worldwide. The test method consists of pushing an instrumented cone, with the tip facing down, the early applications of CPT mainly determined the soil geotechnical property of bearing capacity. The original cone penetrometers involved simple mechanical measurements of the total resistance to pushing a tool with a conical tip into the soil. Different methods were employed to separate the total measured resistance into components generated by the conical tip, a friction sleeve was added to quantify this component of the friction and aid in determining soil cohesive strength in the 1960s.
Electronic measurements began in 1948 and improved further in the early 1970s, most modern electronic CPT cones now employ a pressure transducer with a filter to gather pore water pressure data. The filter is located either on the cone tip, immediately behind the cone tip or behind the friction sleeve. Pore water pressure data aids determining stratigraphy and is used to correct tip friction values for those effects. CPT testing which gathers this data is called CPTU testing. CPT and CPTU testing equipment generally advances the cone using hydraulic rams mounted on either a heavily ballasted vehicle or using screwed-in anchors as a counter-force. One advantage of CPT over the Standard Penetration Test is a continuous profile of soil parameters, with data recorded at intervals typically of 20 cm. In addition to the mechanical and electronic cones, a variety of other CPT-deployed tools have developed over the years to provide additional subsurface information. One common tool advanced during CPT testing is a set to gather seismic shear wave.
This data helps determine the shear modulus and Poissons ratio at intervals through the column for soil liquefaction analysis. Engineers use the wave velocity and shear modulus to determine the soils behavior under low-strain. An additional CPT deployed tool used in Britain, Germany and this is used to attempt to ensure that tests and piles, do not encounter unexploded ordnance or duds. The magnetometer in the cone detects ferrous materials of 50 kg or larger within a radius of up to about 2 m distance from the probe depending on the material, orientation, CPT for geotechnical applications was standardized in 1986 by ASTM Standard D3441
Construction aggregate
Aggregates are the most mined materials in the world. Aggregates are a component of composite materials such as concrete and asphalt concrete, aggregates are used as base material under foundations and railroads. Preferred bitumenous aggregate sizes for road construction are given in EN13043 as d/D, the same classification sizing is used for larger armour stone sizes in EN13383, EN12620 for concrete aggregate, EN13242 for base layers of road construction and EN13450 for railway ballast. These products include specific types of coarse and fine aggregate designed for such uses as additives to asphalt and concrete mixes, state transportation departments further refine aggregate material specifications in order to tailor aggregate use to the needs and available supply in their particular locations. In addition, there are materials that are used as specialty lightweight aggregates, pumice, perlite. People have used sand and stone for foundations for thousands of years, significant refinement of the production and use of aggregate occurred during the Roman Empire, which used aggregate to build its vast network of roads and aqueducts.
The invention of concrete, which was essential to architecture utilizing arches, created an immediate, vitruvius writes in De architectura, Economy denotes the proper management of materials and of site, as well as a thrifty balancing of cost and common sense in the construction of works. This will be observed if, in the first place, the architect does not demand things which cannot be found or made ready without great expense, for example, it is not everywhere that there is plenty of pit-sand, fir, clear fir, and marble. Where there is no pit sand, we must use the kinds washed up by rivers or by the sea. the advent of modern blasting methods enabled the development of quarries, which are now used throughout the world, wherever competent bedrock deposits of aggregate quality exist. In many places, good limestone, marble or other quality stone bedrock deposits do not exist, in these areas, natural sand and gravel are mined for use as aggregate. Where neither stone, nor sand and gravel, are available, construction demand is satisfied by shipping in aggregate by rail.
Additionally, demand for aggregates can be satisfied through the use of slag. However, the available tonnages and lesser quality of these materials prevent them from being a replacement for mined aggregates on a large scale. Large stone quarry and sand and gravel operations exist near virtually all population centers and granite are produced in large amounts as dimension stone. The great majority of crushed stone is moved by truck from the quarry/plant to the first point of sale or use. According to the USGS,2006 U. S. sand and gravel production was 1.32 billion tonnes valued at $8.54 billion, the great majority of this was again moved by truck, instead of by electric train. Currently, total U. S. aggregate demand by final market sector was 30%–35% for non-residential building, 25% for highways, the largest-volume of recycled material used as construction aggregate is blast furnace and steel furnace slag. Blast furnace slag is either air-cooled or granulated, if the granulated blast furnace slag accesses free lime during hydration, it develops strong hydraulic cementitious properties and can partly substitute for portland cement in concrete
Quarry
A quarry is a place from which dimension stone, construction aggregate, sand, gravel, or slate has been excavated from the ground. A quarry is the thing as an open-pit mine from which minerals are extracted. The only non-trivial difference between the two is that open-pit mines that produce building materials and dimension stone are commonly referred to as quarries, the word quarry can include the underground quarrying for stone, such as Bath stone. The surfaces are polished and finished with varying degrees of sheen or luster, polished slabs are often cut into tiles or countertops and installed in many kinds of residential and commercial properties. Natural stone quarried from the earth is considered a luxury and tends to be a highly durable surface. Quarries in level areas with shallow groundwater or which are located close to surface water often have engineering problems with drainage, generally the water is removed by pumping while the quarry is operational, but for high inflows more complex approaches may be required.
For example, the Coquina quarry is excavated to more than 60 feet below sea level, to reduce surface leakage, a moat lined with clay was constructed around the entire quarry. Ground water entering the pit is pumped up into the moat, as a quarry becomes deeper, water inflows generally increase and it becomes more expensive to lift the water higher during removal, this can become the limiting factor in quarry depth. Some water-filled quarries are worked from beneath the water, by dredging, many people and municipalities consider quarries to be eyesores and require various abatement methods to address problems with noise and appearance. One of the effective and famous examples of successful quarry restoration is Butchart Gardens in Victoria, BC. A further problem is pollution of roads from trucks leaving the quarries, to control and restrain the pollution of public roads, wheel washing systems are becoming more common. Many quarries naturally fill with water after abandonment and become lakes, water-filled quarries can be very deep with water, often 50 feet or more, that is often surprisingly cold.
Unexpectedly cold water can cause a swimmers muscles to weaken, it can cause shock. Though quarry water is very clear, submerged quarry stones. Several people drown in quarries each year, many inactive quarries are converted into safe swimming sites
Crushed stone
Crushed stone or angular rock is a form of construction aggregate, typically produced by mining a suitable rock deposit and breaking the removed rock down to the desired size using crushers. It is distinct from gravel which is produced by processes of weathering and erosion. Angular crushed stone is the key material for road construction which depends on the interlocking of the individual stones angular faces for its strength. Crushed natural stone is used similarly without a binder for riprap, railroad track ballast. It may be used with a binder in a material such as concrete, tarmac. Crushed stone is one of the most accessible resources, and is a major basic raw material used by construction, agriculture. Despite the low value of its products, the crushed stone industry is a major contributor to. The demand for crushed stone is determined mostly by the level of activity, therefore. Stone resources of the world are very large, high-purity limestone and dolomite suitable for specialty uses are limited in many geographic areas.
Crushed stone substitutes for roadbuilding include sand and gravel, and slag, substitutes for crushed stone used as construction aggregates include sand and gravel and steel slag, sintered or expanded clay or shale, and perlite or vermiculite. Crushed stone is a high-volume, low-value commodity, the industry is highly competitive and is characterized by many operations serving local or regional markets. Production costs are determined mainly by the cost of labor, equipment and these costs vary depending on geographic location, the nature of the deposit, and the number and type of products produced. Crushed stone has one of the lowest average by weight values of all mineral commodities, the average unit price increased from US$1.58 per metric ton, f. o. b. plant, in 1970 to US$4.39 in 1990. However, the price in constant 1982 dollars fluctuated between US$3.48 and US$3.91 per metric ton for the same period. Increased productivity achieved through increased use of automation and more efficient equipment was mainly responsible for maintaining the prices at this level, transportation is a major factor in the delivered price of crushed stone.
The cost of moving crushed stone from the plant to the market often equals or exceeds the price of the product at the plant. Because of the high cost of transportation and the quantities of bulk material that have to be shipped, crushed stone is usually marketed locally. The high cost of transportation is responsible for the dispersion of quarries
Road surface
Road surface or pavement is the durable surface material laid down on an area intended to sustain vehicular or foot traffic, such as a road or walkway. In the past, gravel road surfaces and granite setts were extensively used, Road surfaces are frequently marked to guide traffic. Today, permeable paving methods are beginning to be used for low-impact roadways and walkways, sometimes called flexible pavement due to the nature in which it distributes loads, has been widely used since the 1920s. The viscous nature of the bitumen binder allows asphalt concrete to sustain significant plastic deformation, most asphalt surfaces are laid on a gravel base, which is generally at least as thick as the asphalt layer, although some full depth asphalt surfaces are laid directly on the native subgrade. In areas with soft or expansive subgrades such as clay or peat. Depending on the temperature at which it is applied, asphalt is categorized as hot mix, warm mix, hot mix asphalt is applied at temperatures over 300 °F with a free floating screed.
Warm mix asphalt is applied at temperatures of 200–250 °F, resulting in reduced energy usage, cold mix asphalt is often used on lower volume rural roads, where hot mix asphalt would cool too much on the long trip from the asphalt plant to the construction site. An asphalt concrete surface will generally be constructed for primary highways having an average annual daily traffic load greater than 1200 vehicles per day. Advantages of asphalt roadways include relatively low noise, relatively low cost compared with other paving methods, in the mid-1960s, rubberized asphalt was used for the first time, mixing crumb rubber from used tires with asphalt. Also, application of rubberized asphalt is more temperature-sensitive, and in many locations can only be applied at times of the year. Study results of the long-term acoustic benefits of rubberized asphalt are inconclusive, compared to traditional passive attenuating measures, rubberized asphalt provides shorter-lasting and lesser acoustic benefits at typically much greater expense.
Concrete surfaces are created using a mix of Portland cement, coarse aggregate, sand. In many cases there will be Portland cement substitutes added and this can reduce the cost of the concrete and improve its physical properties. The water allows the mix to combine molecularly in a reaction called hydration. Concrete surfaces have been refined into three types, jointed plain, jointed reinforced and continuously reinforced. The one item that each type is the jointing system used to control crack development. Jointed plain concrete pavements contain enough joints to control the location of all the expected shrinkage cracks, the concrete cracks at the joints and not elsewhere in the slabs. Jointed plain pavements do not contain any steel reinforcement, there may be smooth steel bars at transverse joints and deformed steel bars at longitudinal joints
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt, Sand can refer to a textural class of soil or soil type, i. e. a soil containing more than 85% sand-sized particles by mass. The second most common type of sand is calcium carbonate, for example aragonite, for example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Sand is a non renewable resource over human timescales, and sand suitable for making concrete is in high demand, in terms of particle size as used by geologists, sand particles range in diameter from 0.0625 mm to 2 mm. An individual particle in this size is termed a sand grain. Sand grains are between gravel and silt, a 1953 engineering standard published by the American Association of State Highway and Transportation Officials set the minimum sand size at 0.074 mm. A1938 specification of the United States Department of Agriculture was 0.05 mm.
Sand feels gritty when rubbed between the fingers. ISO14688 grades sands as fine and coarse with ranges 0.063 mm to 0.2 mm to 0.63 mm to 2.0 mm. In the United States, sand is commonly divided into five sub-categories based on size, very fine sand, fine sand, medium sand, coarse sand, and very coarse sand. These sizes are based on the Krumbein phi scale, where size in Φ = -log2D, on this scale, for sand the value of Φ varies from −1 to +4, with the divisions between sub-categories at whole numbers. The composition of sand is highly variable, depending on the local rock sources. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, arkose is a sand or sandstone with considerable feldspar content, derived from weathering and erosion of a granitic rock outcrop. Some sands contain magnetite, glauconite or gypsum, Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts and obsidian. Chlorite-glauconite bearing sands are typically green in color, as are sands derived from basaltic with a high olivine content, many sands, especially those found extensively in Southern Europe, have iron impurities within the quartz crystals of the sand, giving a deep yellow color.
Sand deposits in some areas contain garnets and other resistant minerals, the study of individual grains can reveal much historical information as to the origin and kind of transport of the grain. Quartz sand that is weathered from granite or gneiss quartz crystals will be angular. It is called grus in geology or sharp sand in the trade where it is preferred for concrete. Sand that is transported long distances by water or wind will be rounded, people who collect sand as a hobby are known as arenophiles
Geotechnical engineering
Geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. A typical geotechnical engineering project begins with a review of project needs to define the material properties. Site investigations are needed to gain an understanding of the area in or on which the engineering will take place, a geotechnical engineer determines and designs the type of foundations, and/or pavement subgrades required for the intended man-made structures to be built. Foundations built for above-ground structures include shallow and deep foundations, retaining structures include earth-filled dams and retaining walls. Earthworks include embankments, tunnels and levees, reservoirs, deposition of hazardous waste, Geotechnical engineering is related to coastal and ocean engineering. Coastal engineering can involve the design and construction of wharves, ocean engineering can involve foundation and anchor systems for offshore structures such as oil platforms.
The fields of engineering and engineering geology are closely related. However, the field of engineering is a specialty of engineering. Humans have historically used soil as a material for flood control, irrigation purposes, burial sites, building foundations, as the cities expanded, structures were erected supported by formalized foundations, Ancient Greeks notably constructed pad footings and strip-and-raft foundations. Until the 18th century, however, no basis for soil design had been developed. Several foundation-related engineering problems, such as the Leaning Tower of Pisa, the earliest advances occurred in the development of earth pressure theories for the construction of retaining walls. Henri Gautier, a French Royal Engineer, recognized the natural slope of different soils in 1717, a rudimentary soil classification system was developed based on a materials unit weight, which is no longer considered a good indication of soil type. The application of the principles of mechanics to soils was documented as early as 1773 when Charles Coulomb developed improved methods to determine the pressures against military ramparts.
By combining Coulombs theory with Christian Otto Mohrs 2D stress state, although it is now recognized that precise determination of cohesion is impossible because c is not a fundamental soil property, the Mohr-Coulomb theory is still used in practice today. In the 19th century Henry Darcy developed what is now known as Darcys Law describing the flow of fluids in porous media, albert Atterberg developed the clay consistency indices that are still used today for soil classification. Osborne Reynolds recognized in 1885 that shearing causes volumetric dilation of dense, modern geotechnical engineering is said to have begun in 1925 with the publication of Erdbaumechanik by Karl Terzaghi. Terzaghi developed the framework for theories of bearing capacity of foundations, in his 1948 book, Donald Taylor recognized that interlocking and dilation of densely packed particles contributed to the peak strength of a soil. Critical state soil mechanics is the basis for many contemporary advanced constitutive models describing the behavior of soil, Geotechnical centrifuge modeling is a method of testing physical scale models of geotechnical problems
Terre Haute, Indiana
Terre Haute is a city in and the county seat of Vigo County, United States, near the states western border with Illinois. As of the 2010 census, the city had a population of 60,785. Located along the Wabash River, Terre Haute is the capital of the Wabash Valley. The city is home to higher education institutions, including Indiana State University, Saint Mary-of-the-Woods College. Terre Haute is notable for being the home of Socialist Party of America leader and five-time presidential nominee and the Federal Correctional Complex. Terre Haute is located alongside the bank of the Wabash River in western Indiana. The city lies about 75 miles west of Indianapolis, according to the 2010 census, Terre Haute has a total area of 35.272 square miles, of which 34.54 square miles is land and 0.732 square miles is water. The Wabash River dominates the geography of the city, forming its western border. Small bluffs on the east side of city mark the edge of the flood plain. Lost Creek and Honey Creek drain the northern and southern sections of the city, in the late 19th century, several oil and mineral wells were productive in and near the center of the city.
That well produced oil into the 1920s, Terre Haute is at the intersection of two major roadways, U. S.40 from California to Maryland and US41 from Copper Harbor, Michigan to Miami, Florida. Terre Haute is located 77 miles southwest of Indianapolis and within 185 miles of Chicago, St. Louis, Climate is characterized by relatively high temperatures and evenly distributed precipitation throughout the year. The Köppen Climate Classification subtype for this climate is Dfa, Terre Hautes name was derived from the French phrase terre haute, meaning Highland. It was likely named by French explorers in the area in the early 18th century to describe the unique location above the Wabash River, at the time the area was claimed by the French and British, these highlands were considered the border between Canada and Louisiana. The construction of Fort Harrison in 1811 marked the beginning of a permanent population of European-Americans. A Wea Indian village already existed near the fort, and the orchards, the village of Terre Haute, a part of Knox County, was platted in 1816.
Growth really began when the founders won the bid to make it the county seat when Vigo County was formed in March 1818. When the villages 1,000 residents voted to incorporate in 1832, Terre Haute became a town, early Terre Haute was a center of farming and pork processing
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