Boundary Conditions On The Stability Of Piers And The Effective Length Of The Impact Analysis And Research

With the development of road transportation enterprise, mountain building Bridges is increasing. Due to the mountainous terrain characteristics as the groove depth, slope steep, bridge piers is often high. But the "highway reinforced concrete and prestressed concrete bridge and culvert design specifications(JTG D62-2004), article 5.3.1 subparagraph(2), only calculate the length factor is the ideal boundary conditions. In fact pier boundary condition is more complex, the pier bottom pile soil non-ideal consolidation. Lateral pier top that with constraints, and its boundary conditions is neither consolidation, nor a hinged.This article mainly from the following two aspects to research the stability of the bridge piers and bridge piers calculated length coefficient values:①When acting on the rigid foundation pile piers, think the pier bottom boundary conditions for consolidation. Bridge pier cap with ordinary plate rubber support, think boundary condition on the top of the pier is elastic connection. The bridge piers under this boundary condition is simplified to an ideal center stressed pole, pier stability equation is derived by static method. Then the finite element software to solve the numerical solution and formula and solution were analyzed. According to the numerical solution of bridge piers calculated length coefficient, and its relationship with high bridge pier, bridge pier size surface figure, by the fitting surface figure out a simplified formula.②When applied to different foundation coefficient of elastic foundation pier pile foundation, said pier bottom boundary conditions for elastic connection. Bridge pier construction stage or have a common plate rubber support, the boundary condition on the top of the pier as pier pier top elastic link or freedom. The bridge piers under this boundary condition is simplified to an ideal center stressed pole, stability equation is derived by using the static method. The numerical solution obtained by finite element software and formula and solution were analyzed.Through the study of this article, the bridge pier is deduced and bottom consolidation pier top for elastic connection, the pier bottom pillar top free for elastic connection or pier top elastic connection of bridge pier under the critical solution formula, numerical verify its correctness. The transcendence of the formula is one of critical load stability equation, the use of Excel software which can be concluded that the critical force calculation length factor are obtained.