Development of Computer Simulator for Rigid Blocks under Earthquake Excitations

通过振动台试验研究了不同尺寸和长细的矩形木砌块和砌块组合在简谐激励和地震基础激励下的反应。在振动台试验之后，进行了分析和数值研究，以建立刚性块的摇摆和倾覆的起始判据。采用离散单元法(DEM)进行数值模拟。通过与试验结果和解析解的对比研究，发现DEM对这一问题具有较好的精度，并进一步利用DEM建立刚性块体的倾覆判据。对一组天然地震的运动进行了数值研究，给出了倾覆与大小、长细比、峰值输入加速度和峰值输入速度的函数关系，该关系可方便地用于内部物体在强震运动下的地震危险性评估。

Shaking table tests were conducted to investigate the response of rectangular wooden blocks and block assemblies of various sizes and slenderness to harmonic and earthquake base excitation. The shaking table tests were followed by analytical and numerical studies in order to estabish criteria for the initiation of rocking and overturning of rigid blocks. The Distinct Element Method (DEM) was employed as a tool of numerical simulation. From the comparison study with the results of the experiments and analytical solutions, DEM was found to have good accuracy for this problem.The DEM was further utilized to establish overturning criteria of rigid blocks. For a set natural earthquake, motions, numerical studies were conducted and a relationship of overturning was proposed as a function of size, slenderness ratio, peak input acceleration and peak input velocity.This relationship may be conveniently used in seismic risk estimation of interior objects subjected to strong earthquake motion.