The Interaction Analysis Of The Soft Soil-piled Raft Foundation-superstructure

With the continuous improvement of China's economic level and the accelerating pace of construction,the problem of having to build complex buildings on soft soil and the goal of optimizing structure and saving resources through joint efforts has gradually become a hot issue.In this paper,the joint action of soft soil foundation-pile raft foundation-superstructure is studied and some useful conclusions are drawn.The main ideas of this paper are two: The first idea is to study the Deformation modulus of different soft soil foundations,the cohesion of different soft soil foundations,the number of different upper structural layers,and the different soft The influence of the internal friction angle of soil foundation on the joint action of soft soil foundation-pile raft foundation-superstructure;The second line of thought adds the role of seismic loading on the basis of the first line of thinking,and studies and analyzes the Deformation modulus of different soft soil foundations,The effects of different soft soil foundation cohesion,different number of superstructure layers,cohesion of different soft soil foundations and different earthquake loads on the joint action of soft soil foundation-pile raft foundation-upper structure.In this paper,through theoretical analysis and finite element numerical simulation,the following main conclusions are drawn:(1)Common design and traditional design contrast,the traditional design has a certain irrationality;(2)Increasing the Deformation modulus of soft soil foundation can effectively reduce the foundation settlement problem,and change the cohesion force to have little effect on settlement;(3)The horizontal displacement of the superstructure decreases with increasing Deformation modulus of soft soil foundation,cohesion of soft soil foundation and internal friction angle of soft soil foundation,and increases with the increase of the number of superstructure layers and seismic loads;(4)Under seismic loading,the axial force at the bottom of the column increases with the increase of the Deformation modulus of the foundation,and the axial force at the bottom of the side column decreases with the increase of the Deformation modulus of the foundation,and the loading occurs in the middle column.With load shedding,the load of the side columns gradually shifts to the middle column,and finally the axial force at the bottom of each column will tend to be equal;(5)Under the action of earthquakes,the axial force at the bottom of one column is increasing,the axial force at the bottom of the column is decreasing,and the maximum axial force appears at the side column.In addition,the seismic load is a back and forth reciprocal load.Therefore,the two side columns The maximum axial force is generated.Therefore,the side column is a structural member that is more dangerous.When the design worker is working on seismic design,it is necessary to design the side column.The innovation of this article:(1)Considering the joint action to calculate the deformation and internal forces of the superstructure,pile-raft foundation,and soft soil foundation can provide reference for design workers and improve the design level of the design;(2)By changing the different factors,we can deeply study the changing laws of the interaction between the superstructure,the piled raft foundation and the soft soil foundation to provide reference for the actual project;(3)The pseudo-static method was used to study the joint action of the soft soil foundation-pile-raft foundation-superstructure under the action of seismic load,and some practical and useful conclusions were obtained,which was conducive to seismic design.