Research On Efficacy Of Rigid-drainage Pile Improvement On Liquefied Lateral Spread Foundation By Shaking Table Tests

Under the action of earthquake,the liquefaction lateral expansion site is prone to horizontal and vertical displacement,resulting in the damage of buildings and structures built on this foundation.In recent years,earthquakes occur frequently all over the world,the liquefaction and deformation of liquefied laterally spread foundation caused by earthquakes are increasingly affecting people's personal and property safety.More and more scholars in the field of geotechnical engineering pay attention to these problems.At home and abroad,a large number of experts and scholars have done a lot of research on the treatment of liquefied lateral spread foundation,including shaking table test and numerical simulation.Professor Liu Han long put forward the treatment method of rigid drainage pile aiming at the problem of anti-liquefaction of foundation.Rigid drainage pile is to increase drainage body on the basis of rigid pile so as to achieve the function of restraining liquefaction of foundation.The drainage performance of rigid drainage pile has been verified,but there is no record for the treatment of liquefaction lateral expansion site.Based on this,in this paper,the rigid pile group is used to treat the liquefaction lateral expansion site.Through the shaking table test and FLAC3 D software,the ability of drainage rigid pile to restrain the liquefaction of the foundation and limit the horizontal and vertical displacement of the foundation is explored.The treatment results of drainage piles are compared with those of ordinary rigid piles.It provides a new idea and method for controlling liquefaction lateral expansion site.The main contents of this paper are as follows:(1)A series of shaking table tests were carried out to obtain the response law of excess pore pressure and foundation,and the effect of rigid drainage pile and common pile on liquefaction lateral expansion site was compared and analyzed(2)On the basis of the conclusion that drainage piles can effectively dispose of liquefied lateral spread site,the arrangement of pile groups is changed,and the corresponding shaking table test is carried out.This paper studies the difference between the quincunx arrangement and the rectangular arrangement of the drainage pile group,and explores the better arrangement of the pile group.The test results show that the quincunx arrangement of pile group is more beneficial to the disposal of liquefaction lateral expansion site,and it has a certain strengthening effect on the control of foundation liquefaction and the limitation of site lateral deformation.(3)In order to verify the correctness of the shaking table test scheme and the reliability of the test results.FLAC3 D software is used for numerical simulation of shaking table test,and numerical simulation software is used to explore the disposal of liquefied lateral expansion site of rigid drainage group.The results show that the response law of the foundation overpressure obtained by shaking table test and numerical simulation is consistent.