Effect of seismic super-shear rupture on the directivity of ground motion acceleration  

作　　者：Hu Jinjun Xie Lili 

机构地区：[1]Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,China Earthquake Administration [2]School of Civil Engineering and Architecture,Harbin Institute of Technology

出　　处：《Earthquake Engineering and Engineering Vibration》2013年第4期519-527,共9页地震工程与工程振动（英文刊）

基　　金：Basic Science Research Foundation of IEM,CEA under Grant No.2011B02;973 Program under Grant No.2011CB013601;National Natural Science Foundation of China under Grant Nos.51238012,9121530113;International Science&Technology Cooperation Program of China under Grant No.2012DFA70810

摘　　要：The effect of seismic super-shear rupture on the directivity of ground motions using simulated accelerations of a vertical strike-slip fault model is the topic of this study. The discrete wave number/finite element method was adopted to calculate the ground motion in the horizontal layered half space. An analysis of peak ground acceleration （PGA） indicates that similar to the sub-shear situation, directivity also exists in the super-shear situation. However, there are some differences as tbllows： （1） The PGA of the fault-normal component decreases with super-shear velocity, and the areas that were significantly affected by directivity in the PGA field changed from a cone-shaped region in the forward direction in a sub-shear situation to a limited near-fault region in a super-shear situation. （2） The PGA of the fault-parallel and vertical component is not as sensitive as the fault-normal component to the increasing super-shear velocity. （3） The PGA of the fault-normal component is not always greater than the fault-parallel component when the rupture velocity exceeds the shear wave velocity.The effect of seismic super-shear rupture on the directivity of ground motions using simulated accelerations of a vertical strike-slip fault model is the topic of this study. The discrete wave number/finite element method was adopted to calculate the ground motion in the horizontal layered half space. An analysis of peak ground acceleration （PGA） indicates that similar to the sub-shear situation, directivity also exists in the super-shear situation. However, there are some differences as tbllows： （1） The PGA of the fault-normal component decreases with super-shear velocity, and the areas that were significantly affected by directivity in the PGA field changed from a cone-shaped region in the forward direction in a sub-shear situation to a limited near-fault region in a super-shear situation. （2） The PGA of the fault-parallel and vertical component is not as sensitive as the fault-normal component to the increasing super-shear velocity. （3） The PGA of the fault-normal component is not always greater than the fault-parallel component when the rupture velocity exceeds the shear wave velocity.

关 键 词：ground motion DIRECTIVITY rupture velocity super-shear rupture peak ground acceleration 

分 类 号：P315[天文地球—地震学]