SUMMARY / RELATED TOPICS

Buckling

In engineering, buckling is the sudden change in shape of a structural component under load such as the bowing of a column under compression or the wrinkling of a plate under shear. If a structure is subjected to a increasing load, when the load reaches a critical level, a member may change shape and the structure and component is said to have buckled. Buckling may occur though the stresses that develop in the structure are well below those needed to cause failure in the material of which the structure is composed. Further loading may cause significant and somewhat unpredictable deformations leading to complete loss of the member's load-carrying capacity. However, if the deformations that occur after buckling do not cause the complete collapse of that member, the member will continue to support the load that caused it to buckle. If the buckled member is part of a larger assemblage of components such as a building, any load applied to the buckled part of the structure beyond that which caused the member to buckle will be redistributed within the structure.

Some aircraft are designed for thin skin panels to continue carrying load in the buckled state. The ratio of the effective length of a column to the least radius of gyration of its cross section is called the slenderness ratio; this ratio affords a means of their failure mode. The slenderness ratio is important for design considerations. All the following are approximate values used for convenience. If the load on a column is applied through the center of gravity of its cross section, it is called an axial load. A load at any other point in the cross section is known as an eccentric load. A short column under the action of an axial load will fail by direct compression before it buckles, but a long column loaded in the same manner will fail by springing outward laterally in a bending mode; the buckling mode of deflection is considered a failure mode, it occurs before the axial compression stresses can cause failure of the material by yielding or fracture of that compression member. However, intermediate-length columns will fail by a combination of direct compressive stress and bending.

In particular: A short steel column is one whose slenderness ratio does not exceed 50. A short concrete column is one having a ratio of unsupported length to least dimension of the cross section equal to or less than 10. If the ratio is greater than 10, it is considered a long column. Timber columns may be classified as short columns if the ratio of the length to least dimension of the cross section is equal to or less than 10; the dividing line between intermediate and long timber columns cannot be evaluated. One way of defining the lower limit of long timber columns would be to set it as the smallest value of the ratio of length to least cross sectional area that would just exceed a certain constant K of the material. Since K depends on the modulus of elasticity and the allowable compressive stress parallel to the grain, it can be seen that this arbitrary limit would vary with the species of the timber; the value of K is given in most structural handbooks. The theory of the behavior of columns was investigated in 1757 by mathematician Leonhard Euler.

He derived the formula, the Euler formula, that gives the maximum axial load that a long, ideal column can carry without buckling. An ideal column is one, straight, made of a homogeneous material, free from initial stress; when the applied load reaches the Euler load, sometimes called the critical load, the column comes to be in a state of unstable equilibrium. At that load, the introduction of the slightest lateral force will cause the column to fail by "jumping" to a new configuration, the column is said to have buckled; this is what happens when a person stands on an empty aluminum can and taps the sides causing it to become crushed. The formula derived by Euler for long slender columns is given below. F = π 2 E I 2 To get the mathematical demonstration read: Euler's critical load where F, maximum or critical force, E, modulus of elasticity, I, smallest area moment of inertia of the cross section of the column, L, unsupported length of column, K, column effective length factor, whose value depends on the conditions of end support of the column, as follows.

For both ends pinned, K = 1.0. For both ends fixed, K = 0.50. For one end fixed and the other end pinned, K = 2 / 2 = 0.7071 For one end fixed and the other end free to move laterally, K = 2.0. K L {\displaystyle K

Znaeš Kolku Vredam

Znaeš Kolku Vredam is the third studio album by Macedonian pop musician, Karolina Gočeva. The album was released in Macedonia and in Serbia, Bosnia & Herzegovina under the Serbo-Croatian title Kad Zvezde Nam Se Sklope... Kao Nekada. "Hipokrit" "Ljubov Pod Oblacite" "Od Nebo Do Dno" "Ne Se Plašam" "Znaeš Kolku Vredam" "Sirena" "Noќ" "Štom Sakaš" "Ljubovta E Moja Religija""Srešćemo Se Opet" Cover Vlado Janevski Nekogas i negde Female Singer Of The Year Album Of The Year Song Of The Year Concert Of The Year Music Video Of The Year Choice Of The Audience Female Singer Of The Year Album Of The Year Music Video Of The Year Female Singer Of The Year Music Video Of The Year Song Of The Year

1993–94 Colchester United F.C. season

The 1993–94 season was Colchester United's 52nd season in their history and their second consecutive season in the fourth tier of English football, the Third Division. Alongside competing in the Third Division, the club participated in the FA Cup, the League Cup and the Football League Trophy. Following a 10th-placed finish the previous campaign, Colchester's defensive frailties were clear as they shipped 71 goals, the second-highest in the league and ended the season in 17th, they crashed out of the FA Cup to non-League opposition in Sutton United, while Fulham saw off the U's in the first round of the League Cup. In the Football League Trophy, Colchester progressed to the southern section quarter-final but were eliminated by old Conference rivals Wycombe Wanderers. Following a campaign of goalkeeping uncertainty where the U's employed six different'keepers over the course of the season, finding a regular starter between the sticks was key for manager Roy McDonough. With youth team product Nathan Munson on the books, McDonough brought in John Keeley from Oldham Athletic in the summer.

However, his performances did not convince and he played his final game for the club in November 1993. This meant a string of mid-season transfers and loans of goalkeepers into the club, the U's ended the season having once again used six different goalkeepers. McDonough found himself in goal in October 1993 when facing Hereford United after Keeley and substitute Munson were both sent off for professional fouls; the U's went on to lose that game 5–0. Colchester were the first Football League club to have two goalkeepers sent off in the same fixture. Hereford striker Chris Pike scored a hat-trick in the game, with each of his goals coming against three different goalkeepers; the fans frustration at the defensive performances came to a head in the FA Cup first round. The U's found themselves 2–0 down at home to non-League side Sutton United, before goals from Steve McGavin and Steve Brown levelled the score at 2–2 early in the second half. Sutton struck again in the 84th minute. Despite their best efforts, two-minutes from time, Ollie Morah scored the winner for Sutton to send them into the second round.

The financial situation was bleak. There were no funds to bring in a permanent goalkeeper, striker Steve McGavin was sold to Birmingham City for £150,000 in January. Again, no funds were made available for a replacement, it took a consortium of local businessmen to raise £10,000 to buy Steve Whitton from Ipswich Town on deadline day to fill the gap. As such, the U's ended the season in a disappointing 17th-position in Division Three. There was an early exit from the League Cup as Fulham beat Colchester over two legs in the first round, while in the Football League Trophy, the U's progressed from the first round group stage beat Wrexham in the second round, before falling to defeat in the southern section quarter-final at home to Wycombe Wanderers, who won 1–0. Roy McDonough was handed a silver salver by chairman Gordon Parker on the last day of the season in recognition of McDonough's 500th career appearance. Three days it was Parker, McDonough's father-in-law, that sacked him; as of match played 7 May 1994.

Total spending: ~ £20,000 Total incoming: ~ £0 Qualified for next round Number of games goalkeepers kept a clean sheet. Players making their first-team Colchester United debut in a competitive match. List of Colchester United F. C. seasons Books Whitehead, Jeff. The Who's Who of Colchester United: The Layer Road Years. Derby: Breedon Books. ISBN 978-1-85983-629-3. Websites "Colchester United football club match record: 1994". 11v11.com. Retrieved 22 August 2018