Ground Motion Prediction for Urban Earthquake Disaster Mitigation

本研究项目的目的是开发用于工程设计和评估的近断层地震动特征的方法。需要解决的具体问题包括近断层破裂的方向性效应和盆地边缘效应。这两种效应被认为是1994年北岭地震和1995年神户地震破坏性地面运动的主要原因。这个项目涉及与京都大学的Irikura教授和来自其他几个日本研究机构的同事的协作，首席研究人员与这些研究机构有着长期的协作关系。具体目标包括：(1)制定改进的震源特征描述程序，用于预测未来地震的近断层强地面运动；(2)制定改进的近断层地面运动模拟程序，包括引起盆地边缘效应的地下基岩地形等复杂结构的影响；利用时间域特征和频谱特征，改进近断层地面运动的表示形式，用于工程分析和设计。最后一项任务是与斯坦福大学的Helmut Krawinkler教授合作。预计这项研究将导致：(1)具有良好的理论和经验基础的可靠程序，用于产生用于实际设计和评估的近断层地震运动；(2)改进的一套用于描述近断层地震运动的地面运动参数；以及(3)改进近断层地震运动的表示；使用近断层地震运动时间历史集和简化的近断层脉冲，用于设计。

The objective of this research project is to develop methods for characterizing near-fault ground motion for use in engineering design and evaluation. The specific issues to be addressed include near-fault rupture directivity effects and basin edge effects. These two effects have been identified as principal causes of the damaging ground motions in the 1994 Northridge and 1995 Kobe earthquakes. This project involves a collaboration with Professor Irikura of Kyoto University and colleagues from several other Japanese research organizations, with whom the Principal Investigators have a long term collaborative relationship.Specific objectives include: (1) develop improved procedures for earthquake source characterization for use in the prediction of near-fault strong ground motion of future earthquakes; (2) develop improved procedures for simulating near-fault ground motions, including the effects of complex structure such as subsurface bedrock topography that cause basin edge effects; develop an improved representation of near-fault ground motion for use in engineering analysis and design, using time domain characteristics in conjunction with spectral characteristics. The last task involves collaboration with Professor Helmut Krawinkler of Stanford University.It is expected that this research will lead to: (1) reliable procedures, having a sound theoretical and empirical basis, for the generation of near-fault ground motions for use in practical design and evaluation; (2) an improved set of ground motion parameters with which to describe near-fault ground motions; and (3) an improved representation of near-fault ground motions; using sets of near-fault ground motion time histories and simplified near-fault pulses, for use in design.