Dynamic Interaction Test And Numerical Simulation Of Pile-soil-structure

Pile-soil dynamic interaction is a very important and complex issue.In order to deeply study the mechanical behavior and failure mechanism of pile foundations,shaking table model tests of three-layer steel frame structure pile soil system and three-layer concrete structure pile soil system were carried out in this paper,and the finite element software ABAQUS was used to numerically simulate the test model.The specific research work and achievements are as follows:1.Overview of current research on soil structure interactionThe research status and achievements of soil structure interaction at home and abroad are summarized in detail,and the research methods of soil structure interaction at home and abroad are summarized and compared.The main research progress of large-scale shaking table tests in China is introduced,and the main research content of this article is clarified.2.Shaking table model tests of three-layer steel frame structure pile soil system and three-layer concrete structure pile soil systemA series of shaking table tests of three-layer steel frame structure pile soil system and three-layer concrete structure pile soil system have been designed and completed.Through observing the macro phenomena of the test and detailed analysis of the test data under various test conditions,the dynamic interaction rules and structural failure conditions of different superstructure pile soil systems have been summarized.The results show that the predominant period of the response spectrum of the pile soil steel frame structure model system is longer than that of the pile soil concrete structure model;Steel frame structures,compared to concrete structures of the same height and size,have smaller mass and stiffness,making them more responsive to the same seismic action.However,in concrete structure systems,the soil is more prone to cracking,causing separation between the foundation and the soil,causing significant deformation of the pile foundation,and making it prone to damage.Each pile in the pile group has suffered varying degrees of damage,with the most severe damage occurring at and near the connection between the pile foundation and the pile cap.After exceeding 4-7 times the pile diameter.The failure mode of the pile body is bending tensile failure.3.Finite element analysis of shaking table models for pile soil system,three story steel frame structure pile soil system,and three story concrete structure pile soil system.The finite element software ABAQUS was used to establish the upper structure pile soil model in the vibration table test.Through the comparison and analysis of the numerical simulation calculation and experimental results using the finite element software,the surface numerical simulation calculation results and experimental results were well matched,verifying the accuracy of the finite element modeling method andprocess,as well as the rationality of selecting relevant material parameters.Supplementary calculations were made for the working conditions not involved in the test,The results show that for a pile soil system without a superstructure,the impact of input seismic amplitude changes on the acceleration amplification coefficient of the pile foundation is very small and can be ignored;Compared to the pile soil system and the three-layer steel frame structure pile soil system,due to the high quality and stiffness of concrete structures,the inertia force generated is large.The deformation of the pile foundation in the three-layer concrete structure pile soil system is significant,and the foundation is more prone to damage.