Research On The Influence Of Integral Foundation Sliding To Mechanical Properties Of The Bridge And The Reinforcement Method Based On The LS-DYNA

The structure of the bridge in the sliding zone is complicated,because of the complex interaction of the bridge pile and the surrounding soil.Currently existing research is all about force analysis of bridge pile in sliding zone.However,there are few references to the analysis of the influence of the foundation sliding on the overall structure of the bridge.This paper simulates the influence of the foundation sliding on the overall performance of the bridge by finite element and the reliable reinforcement treatment measures are put forward combining with the results of the analysis.In this paper,main work are as follows:(1)It studies mechanical properties of the bridge pile foundation,pier and girder mechanical properties using LS-DYNA and analyzes the response of bridge from the aspects of the deformation,stress and contact force of each part of the bridge.(2)It analysies different factors for the response of the bridge under basal sliding on and studies the influence of different section size of pile foundation,pile length ratio and different elastic modulus of pile foundation from two aspects of displacement and stress.(3)The finite element numerical analysis method is used to study the effect of soil arch between piles to prove the existence of the soil arch and its effect,and to reveal the mechanism of the anti slide pile and the landslide rock mass.It establishes the model of bridge-anti slide pile-soil mass compared with the whole model results without anti slide pile,in order to illustrate the practical effect of anti-slide pile.Through the above analysis,the conclusion is drawn:(1)Foundation sliding has great influence on the whole bridge: There is a lateral deflection of the bridge,the top position of the pier is the largest,the main girder and the pier has a larger displacement difference,which is the direct cause of the bearing damage and even the beam.There is a large moment,in the pile foundation close to the bedrock sliding surface in the vicinity,resulting in large tensile stress due to the location on the upslope side,exceeds the ultimate tensile strength of concrete,local has been broken due to the effect of landslide thrust,the bedrock sliding surface in the vicinity of the pile foundation is located in the big moment,resulting in large tensile stress due to the location on the upslope side,exceeds the ultimate tensile strength of concrete,local has been broken.(2)Bridges response under different influence factors.With the increase of section size of pile foundation,pile length ratio and deformation modulus of pile,there is a different change trend in stress and displacement of girder,pier and pile foundation,which has a far-reaching significance on the design.of the bridge in the landslide.(3)Based on the establishment of the anti slide pile soil model,the deformation characteristics of the soil are analyzed.Under the action of the landslide,the displacement of the soil after the pile is squeezed between the piles due to the block of the pile,which proves the uneven deformation of the pile and the soil,which is the necessary condition of the soil arch.By analyzing the whole model of bridge anti slide pile,it is known that the displacement and stress of bridge are greatly reduced after setting anti slide pile,the anti sliding effect of the anti slide pile is fully explained.As a result of the existence of anti slide pile,the landslide thrust of bridge pile foundation is reduced a lot.