Torsional And Rocking Response Of Building Foundation Induced By Obliquely Incident S Waves

In the seismic design and analysis of building structures,it is often assumed that the structural foundation and the ground move synchronously during the earthquake without considering the interaction between the foundation and the surrounding soil.In many cases,the above assumption cannot accurately predict the dynamic response of the superstructure under earthquakes.Therefore,it is of great significance to consider soil-structure interaction in seismic design and analysis.However,it was generally assumed that seismic waves were vertically incident in previous studies on soil-structure interactions.This assumption has some applicability to deep-focus earthquakes,but it may bring some errors for shallow earthquakes.Based on this,study on the dynamic response of building structures induced by spatial incident seismic wave from any angle is one of the scientific problems urgently to be solved in civil engineering.In this thesis,the torsional and rocking response of the building foundation induced by obliquely spatial incident shear wave from any angle are studied systematically.Combined with Fortran programming,the viscous-spring artificial boundary and the input of obliquely incident shear wave is realized in the three-dimensional finite element model of ABAQUS.This provides an effective wave input method for studying the dynamic response of building foundation to obliquely incident shear wave.The effect and accuracy of the input method is confirmed by comparing with the theoretical results.Based on the finite element analysis,this thesis first studies the characteristics of torsional and rocking response of square foundation on the obliquely spatial incident shear wave.Meanwhile,the torsional and rocking response of a 7-story frame were analyzed under the impact of obliquely incident EL-Centro waves.The analysis results show that the spatial incident angle of the shear waves has significant effect on the amplitude of the torsional and rocking response of the superstructure.This analysis further confirms that the study on the soil-structure interaction is of great practical significance under the impact of obliquely incident shear wave.Then,the torsional and rocking response of rectangular,L-shaped and C-shaped foundation are analyzed systematically with the variety of spatial incident angle of the shear wave.The results show that the torsional and rocking response of the foundation will change greatly with the variety of the incident direction and the vibration direction of the incident shear wave.Finally,the impact of the shape parameters of rectangular,L-shaped and C-shaped foundations on the torsional and rocking response to obliquely incident shear waves is analyzed.The results show that there are some limitations on the study of the dynamic response of irregular foundation without considering the shear wave vibration direction.