摘要
近断层地震动受地震震源参数的影响显著,基于典型的地震有限断层模型,通过离散波数有限元数值模拟方法,计算了断层上可能的三种不同初始破裂位置条件下的一系列地表场点的地震动时程,比较不同初始破裂位置对地震动参数的影响,结果表明:1初始破裂位置越靠近地表,地震动的峰值越大,而且初始破裂位置对地震动的加速度影响最大,对速度和位移的影响较小;2对地震动不同分量的分析表明,初始破裂位置对地震动的垂直断层分量影响较大,对平行断层和竖向分量影响很小;3初始破裂位置深度的增大会降低地表地震动的幅值,但是断层破裂不同方向上的地震动幅值相对差异仍然存在。因此,断层面上的初始破裂位置也是地震动模拟和预测中需要考虑的一个重要因素。
The near-field ground motion is seriously affected by source parameters of earthquake. Based on a typical finite fault model,by using a discrete wavenumber finite element method,the time histories of ground motion were calculated with different initiatial rupture locations. Through the analysis of typical ground motion parameters,the results indicate： the closer the initiatial rupture location to ground surface,the greater the peak value of the ground motion; the acceleration is much more sensitive to the initiatial rupture location than the velocity and displacement; the fault-normal component is more sensitive to the initial rupture location than the fault-parallel or vertical component; although the location of initiatial rupture may affect the amplitude of ground motion,the directivity features of ground motion still exist in different situations. Thus,the location effect of initial rupture of earthquake source should be considered for ground motion modeling and prediction.
出处
《振动与冲击》
EI
CSCD
北大核心
2015年第24期66-70,共5页
Journal of Vibration and Shock
基金
国家自然科学基金重点和面上项目(51238012
51578516)
国家重点基础研究发展计划项目(2011CB013601)
国家国际合作项目(2012DFA70810)
黑龙江省青年科学基金(QC2011C058)
中国地震局工程力学研究所基本科研业务专项(2011B02)
关键词
地震断层
初始破裂位置
地震动参数
数值模拟
earthquake fault
initiatial rupture location
ground motion parameters
numerical modelling
