The Theoretical And Experimental Research Of Mechanical Behavior Of The Bridge Pile Considerring Slope Effect

With the implementation of the western development strategy in our country,in order to meet the requirements of people for transportation and convenient,more and more bridge pile foundation of high-speed railway and highway tunnel are built on loess slope inevitably.Due to the influence of the interaction between piles and loess slope,the side-slope pile shows the different features comparing with the level-ground pile,which makes it own the characteristics of active pile and passive pile.So the ground-pile foundation theory and experience are not suitable for the pile foundation in the loess slope,which makes it lack of design code and the guidance of safety supervision for this type of pile foundation in practical engineering.In this paper,the bearing mechanism and mechanical characteristics of pile foundation considering the influence of loess slope are analyzed systematically combining with the science and technology development program of the China Railway Corporation--Study on mechanical behavior and design theory of pile foundation of high speed railway bridge on loess slope in Northwest China.Comparing with the ground-pile foundation,the bearing mechanism,the stress characteristic and the failure mode of the pile foundation which is built on the loess slope are quite different,he main contents of this paper as follows:(1)The research methods of potential landslide thrust is from the anti-slide pile.According to the beneficial results in both at home and abroad,it chooses the reasonable distribution mode of soil thrust on the loess slope.(2)On the basis of the stress of level-ground pile,the force analysis is done to the bridge pile foundation on loess slope considering the slope effect,which can obtain the differential equations of bridge pile.The finite difference method is applicated to solve it.(3)The influence factors of slope effect are analyzed,considering the different distribution of landslide thrust mode,different slope Angle of slope on the bridge the influence of the internal force and displacement of pile foundation.(4)Outside the loess slope bridge pile foundation test,at the same time under the action of vertical load and horizontal load of three groups of six loading test of root pile foundation,pile foundation pile top horizontal displacement and pile body stress value.(5)FLAC 3D numerical model was established based on the experiment,the numerical simulation results with experimental results analyzed,went into depth on the bearing capacity,pile foundation coefficient and the relationship between slope distance.