强地面运动数值模拟中三维物理模型的建立方法——以昆明盆地为例

基于活动断层的地震危害性综合评价可为城市规划和工程建设提供科学依据， 强地面运动数值模拟则是进行地震危害性预测和评价的重要方法， 而建立以第四系为主体的符合真实地层结构的三维物理模型是保证数值模拟结果可靠性的必要条件之一. 本文以昆明盆地为例， 综合利用地震地质、钻孔、地形地貌、DEM、地震勘探、波速测试等资料，以剪切波速为主要分层指标，参考地层层序， 结合ArcGIS等多种软件和相关的编程技术，采用将相邻介质分界面（层网）在深度方向上逐层叠加的方法建立三维物理模型；详细阐述了建立三维物理模型的主要技术思路和实现过程， 同时建立三维物理模型的数据库，为强地面运动数值模拟提供模型数据和参数. 文中还针对不同类型的探测、实验数据，总结了相应的技术处理方法和需要注意的问题. 

3-D PHYSICAL MODEL IN STRONG GROUND MOTION NUMERICAL SIMULATION: A CASE STUDY OF KUNMING BASIN

Seismic hazard assessment based on urban active faults can provide scientific bases for city planning and project construction, while numerical simulation of strong ground motion is an important method for seismic hazard prediction and assessment. A 3-D physical model in conformity with real strata configuration of (mainly) the Quaternary is a prerequisite to ensure the reliability of the simulation results. In this paper, we give a detailed account of the technical scheme and process for creating a 3-D physical model in Kunming basin. The data used are synthesized from seismogeological data, borehole data, topographic data, digital elevation mode (DEM) data, seismic exploration results and wave velocity measurements. Stratigraphic division is based mainly on shear wave velocity, with strata sequence taken into consideration. The model construction is finally accomplished with ArcGIS and many relevant programming techniques via layer-by-layer stacking (in depth direction) of the adjacent medium interfaces (meshes). Meanwhile, a database of 3-D physical models is set up, which provides model data and parameters for strong ground motion simulation. Some processing methods and significant issues are also addressed in the paper in accordance with different types of exploration and experimental data.