Study On Forced Deformation Of Pile Foundation Of Site And Adjacent Bridge Piers By Large Area Loading In Soft Soil Area

Lakes and sea areas are widely distributed in the southeastern coastal areas of China,and there is a shortage of land resources.At the same time,cross-sea bridges and land connection projects often exist in these areas.When carrying out these construction activities,they are often accompanied by cross-construction and bridge construction activities phenomenon.In order to meet the needs of these constructions,the piled-up projects such as embankments and dikes have become one of the important ways to alleviate the contradiction between supply and demand of construction land.However,the geological conditions in the coastal areas are complex and mostly deep soft clay,and the lateral deformation of the lower soil caused by the loading is large.This will cause a large horizontal pressing force on the adjacent bridge pile foundation,which will cause lateral displacement of the pile foundation.If the offset is serious,it will seriously affect the safe use of the bridge superstructure.Therefore,it is necessary to study the horizontal displacement of the foundation soil under the action of pile load and the additional bending moment and lateral deformation law of the pile foundation of adjacent piers.Based on the engineering background of the construction of a large-scale dike in Zhejiang and the adjacent bridge pier piles(vertical embankment and bridge vertical),based on the principle of interaction between soil layer and pile foundation,the ABAQUS finite element software is used to establish the pile-foundation soil.The three-dimensional finite element solid model of the body-pile foundation is used to investigate the lateral deformation of the piled soil and the adjacent pile foundation.The main work is as follows:(1)The lateral deformation mechanism of foundation soil and pile foundation under the action of pile-loading is analyzed from the theoretical direction.The theory of horizontal displacement field of soft soil foundation and pile body deformation under adjacent pile foundation is summarized.And experimental research.(2)Using ABAQUS to establish a three-dimensional finite element model of the pile-site-bridge pile foundation,for the loading parameters(loading height,loading position,stacking slope),soft soil geotechnical parameters(compression modulus,Poisson’s ratio),internal friction angle),pile foundation parameters(relative stiffness of piles and soils,pile foundation caps)are analyzed to explore the lateral deformation of the site under the influence of different parameters and the additional bending moment and lateral deformation characteristics of the pile foundation of the pier,and summarize The influence law of different parameters.At the same time,corresponding measures are proposed for the large-scale pile-up of soft soil foundation,so that the lateral deformation of the bridge pier pile meets the control requirements.(3)The engineering examples of the cross-construction of the dam of a certain reclamation area in Zhejiang and the pile foundation of the 12# bridge pier are analyzed.In order to compare and analyze the force deformation behavior of the soil before and after the foundation treatment and the pile foundation of the 12# bridge pile,the soil under the condition of unreinforced foundation,foundation reinforcement and foundation reinforcement on the basis of the pile foundation of the concrete-filled pile is studied.The force deformation of the pile foundation of the pier.At the same time,based on relevant specifications and research,the maximum horizontal displacement of 12# pier pile foundation under three working conditions was evaluated.