Analysis Of The Force Mechanism Of Pile And Soil Under Inclined Loading

With the development of economy and the needs of a growing population,promoted the great-span bridges and the rapid development of high-rise buildings,analysis of pile under inclined load or axial and lateral loads under stress condition is becoming more and more important.At present,the study of stress mechanism of the pile under inclined load is only confined to the role of macroeconomic level,and for the pile foundation under inclined load of pile and soil particle relative motion,the micro level study of the interaction is less.The soil is composed of broken loose granular composition,non-linear,non continuous features,so the mechanism from the micro level study of the interaction of pile and soil is very necessary.This paper is based on the single pile static load test in sand.Based on the discrete element method to simulate the pile under inclined loads.The pile and the soil around the pile as a discrete particle assembly,using particle flow code(PFC)simulation test of pile under inclined loads interaction mechanism.By setting the measurement of circular around pile and the different nature of soil around pile,discussed the mechanism at the micro level of interaction between pile and soil.This paper mainly completed the following work: Firstly,simulation of the single pile static load test of model in sand,establishment of PFC particle flow simulation model.Focuses on the analysis of pile under inclined loads,change of displacement of soil around pile particle and force chain transfer of pile and the soil pressure.And analyzes the influence of friction coefficient of granular,pile diameter and soil rigidity of soil pile interaction.The results show that the:(1)The free end of the short rigid pile under load,the soil particles before the pile,first show lateral translation from the pile a certain distance,is upward movement.(2)With the increasing of pile top load,the pile effect range of the pile and soil stress and the influence range of the soil at the end increases,depth of pile decreases.The pile turning point moving to pile before gradually.(3)With the increase of the pile diameter,the influence on the pile end soil gradually decreases and the displacement of the soil around the pile body increases gradually;the settlement gradually decreases,the distance of pile turning point moving to pile before decreases;the pile soil pressure is gradually increased with the depth of pile.(4)With the increase of the soil particle stiffness,displacement of soil particles around piles decreases,the influence on the pile end soil increased gradually;the pile settlement decreases gradually,the soil around the pile stress increases;the pile by pile particle constraint,the rotation point is not obvious and move in front of the pile distance decreases.(5)With the increase of the friction coefficient of soil particles,the settlement gradually decreases and tends to be equal,according to the force chain transfer,the pile end soil on vertical soil pressure is reduced,increasing the pile lateral soil pressure;the rotation point gradually moves to behind the pile.