Dynamical Effect Of Vehicle-bridge Interaction To Bridge And Its Influence On Slope Stability Under Pile Foundation

In the research of vehicle-bridge interaction bridge vibration arising from traffic load and its influence on environment has caused abroad attention. Tall piers and large spans structures were built especially in mountainous areas, where most of bridges strode over cloughs. Vehicle load cause the vibration of bridge and tall piers which certainly will result in great stability influence upon slope under tall piers ,some slides occur large deformation ,some occur unstable and landslide even dilapidation . Therefore vehicle-bridge interaction influence on slope stability under pile foundation is a new task of deserved research.When tall piers and large spans bridges with the representative of Lizi Channel Bridge are under the vehicle load, transfer the load from vehicle to bridges, from foundation to slope. So two three-dimensional analysis models for spans and piers departments of the bridge and for foundation-bank slope were set up respectively in the course of analysis. The total analysis method is finding the bridge's vibration situation and maximal reverse force under the pier through dynamical analysis to the bridge. Then the maximal reverse force under the pier is loaded on the pier of the second system model, which can get the deformation and behavior of the slope. And prestressing cable were adopted to guarantee the slope stable.These series complex issues come down to both vehicle-bridge interaction and pile-soil interaction, so theories and methods according with fact must be applied in order to solve the issues. The key of the spatial vibration analysis is how to deal with exiting source. Vehicle-bridge interaction takes track irregularity as exiting source usually. In this paper vehicle-bridge interaction based on power spectrum density theory is adopted. Power spectrum density of acting force between wheel and track on different grade railway is confirmed based on statistic characteristic of acting force between wheel and track, and then loading to the bridge. In the second model contact nonlinear theory is introduced between pile and soil, namely friction pile according with the fact is considered. Constitutive model of the slope soil is nonlinear material constitutive relation, which can truly express behavior and deformation when the soil reaches elasticity-plasticity or plasticity state. At the same time reinforcing theory of prestressed cable is adopted to strengthen the slope and guarantee the stability of theslope. Some helpful regulations and conclusions eventually are gained which can provide reference and evidence for practice engineering.