The Analysis Of Geometrical Nonlinear Behavior Of Long-Span Continuous Rigid Frame Bridge With High-Pier

In the recent years, long-span bridge with high-pier has been growing up rapidly with the development of transportation enterprise. Long span continuous rigid frame bridge with thin-walled high piers' is commonly built in China, owning to their advantages on economy and construction. However, the stability problem of the bridge, especially in the stage of cantilever construction is more remarkable.The nonlinear behavior of bridge becomes more and more important with the increase of its span and pier height. This thesis illustrates the geometrical nonlinear theory of bars system, introduces the spatial description methods of structural shapes of geometrical nonlinear behavior and emphasizes the discrimination between Total Lagrangian Formulation and Updated Lagrangian Formulation in Lagrangian Formulation.Based on Labajin Bridge, this thesis focuses on the nonlinear of continuous rigid frame bridge with high Piers during the construction of cantilever, by use of finite element program Midas/Civil. The calculation indicates that geometrical nonlinear effect affects obviously to Y-direction displacement of the bridge, through straight,curved and single lane,double lanes of the comparison . In the straight bridge and the curved bridge structure there is very big difference in the displacement distortion and the structure stress. The straight bridge does not have the lateral displacement and the Z direction bending moments, but the curved bridge can have the lateral displacement and Z direction bending moments.There is very big difference between the linear and nonlinear analysis results, which shows that the high-pier and long-span bridge is very necessary to consider geometrical nonlinear analysis.