地震动是由3个物理过程(震源破裂过程、波传播过程、场地反应)组成的一种复杂系统的产物,地震动模拟均是围绕这3个物理过程的建模开展的。地震动模拟目前仍然是一门相对较新的科学,强震观测中不断发现的新情况、新问题及其深入研究进一步推动近断层地震学理论和实践的发展。减少建模中的不确定性,用基于观测物理学的统计特征逐渐取代基于现象的假设描述,以改善地震动模拟的精度。基于大量地震动模拟的研究文献和资料,归纳、评述了近断层地震动模拟方法的现状、3个物理过程的建模方法及其发展趋势。
The ground motion is the outcome of a complicated system that consists of three physical processes (i. e. , earthquake source rupture process, seismic wave propagation, and site response), and is simulated based on modeling the three physical processes. The ground motion simulation is a relative new discipline. New cases and problems discovered progressively in strong motion observation and lucubrated on them will further promote development of both theory and practice about near-fault seismology. The precision in ground motion simulation will be improved by both reducing uncertainties in models and substituting statistical characteristics based on observation physics for hypotheses based on some phenomena. The present situation of simulation methods of near-fault ground motion, methods of modeling three physical processes, and their trends are reviewed based on a lot of literatures and data on ground motion simulations.