Seismic Response Analysis Of High Buildings Considering Soil-Structure Interaction

Traditional anti-seismic design method is often used in Construction Design Regulations, which supposes that the ground is rigid. The method is convenient and feasible. For the seismic design of buildings, there will be errors based on the rigid ground hypothesis and this assumption does not conform to the actual condition when the superstructure rigidity is close to the foundation. As the high buildings increase greatly, it is necessary to analysis and study the further the pile-soil-structure dynamic interaction under seismic excitation, which will offer theoretical basis for the design and analysis of structure.Considering and un-considering the soil-structure interaction under seismic excitations are contrasted and analyzed by using 2-D elastic-plastic method with ANSYS finite element analysis software. In contrast with the maximums of force, displacement, acceleration of floors, this paper studies structural response regularity after considering interaction and discusses superstructure rigidity change's impact on interaction. The main contents and conclusions of this paper can be described as follows:Firstly, based on related materials and literatures, the research and development state of soil-structure interaction at home and abroad is also elaborated. The second section, the theoretical analysis method of dynamic interaction is summarized generally. The third section, this paper discusses the constitutive relation models of superstructure and soil. In this paper Drucker-Prager elastic-plastic model is chosen to simulate soil in ANSYS. Besides, bilinear isotropic hardening elastic-plastic constitutive model is applied to the superstructure. Next part is a calculation example about seismic response analysis. The finite element model of pile-soil-structure interaction is constructed and solved in the ANSYS platform. The contact element is established between pile and soil. And the boundary is free, the soil bottom is restrained, then the entire system is exerted in inertial force. The results show that after interaction consideration, the maximum displacements have increased, while the maximum relative displacements have reduced. Also the maximums of the acceleration, the shear force and the axial force have reduced to varying degrees, the superstructure rigidity's influence on interaction is also discussed. The analysis indicates that it is crucial for dynamic analysis to consider interaction under horizontal seismic excitation.