Seismic Performance Analysis Of High Pile Wharf In Reinforced Liquefying Ground

As an important key node of transportation infrastructure,the port and wharf project is an important supporting project for the implementation of the “Belt and Road” initiative.However,most important ports are located in the seismic zone along the “Belt and Road”.The liquefaction of foundation soil is one of the main causes of the structural damage of port terminal.Therefore,improving the seismic disaster mitigation and liquefaction prevention and control performance of port terminals is a challenge at present,and foundation reinforcement is the main method to effectively prevent and control foundation liquefaction.At present,scholars at home and abroad have done many research on the seismic performance analysis and foundation treatment of the port terminal,but most of the research is only for the seismic measures of wharf structure,and there are few systematic studies on the influence of foundation treatment behind the wharf on the seismic performance of the wharf.Also,most of the research about foundation treatment of port wharf focuses on common measures such as stone column or prefabricated vertical drains,but the application of geosynthetic-encased stone column in high-piled wharf engineering has not been studied.In view of this,based on the finite difference numerical calculation method,this paper takes the high-piled wharf,a common wharf structure form,as the analysis object,and uses stone column and geosynthetic-encased stone column respectively to reinforce the foundation behind the crest of the slope,analyzes and evaluates the seismic performance of the high-piled wharf in liquefying ground.The main work is summarized as follows:Firstly,based on the typical centrifuge shaking table test of high-piled wharf,a three-dimensional finite difference numerical model of high-piled wharf in liquefying ground is established,and the dynamic response of the piled wharf under seismic load is obtained.The grid division of numerical model,material constitutive model,boundary conditions and other calculation parameters,as well as the realization process of static and dynamic calculation are mainly studied.Then,compared the test and numerical results to verify the correctness of the numerical simulation.Then,based on the verified numerical simulation method,a three-dimensional finite element model of high-piled wharf with stone column composite foundation in liquefying ground is established.By using the single factor variation analysis method,the influence of parameters such as the distance between the reinforcement area and the wharf B,the area replacement rate M of stone column,the pile diameter D and the ratio L of pile length to the thickness of liquefiable soil layer on the reinforcement effect of stone column is studied.Finally,the geosynthetic-encased stone column is used to reinforce the foundation of the high-piled wharf,and the parameter analysis is carried out with the same parameters as the stone column working condition.Then,the reinforcement effect of the stone column and the geosynthetic-encased stone column is analyzed and evaluated from the excess pore pressure ratio and deformation of the soil,the dynamic response of the deck and the pile foundation of wharf.The results show that the geosynthetic-encased stone column is more conducive to improve the seismic performance of high-piled wharf in liquefying ground.