不同土质条件下断层地表破裂对比研究

本文结合华北地区几个地震统计区的实例,探讨了地震统计区的重要地震活动性参数b值和v4不确定性的主要影响因素及其特征,并研究分析了其不确定性的大小。结果表明,地震活动性参数的不确定性主要影响因素为样本统计时段、样本处理方法、统计下限震级、高震级年平均发生率等。在郯庐地震统计区,b值变化可达0.2以上,v4的变化可达1.4以上,汾渭地震统计区的不确定性也基本相当,河北平原地震统计区因为地震样本相对丰富,不确定性要小许多。

Comparative Study on Surface Rupture of Faults in Different Soil Mass

Elasto-plastic finite element model has been set up for the study on surface rupture of different soil mass above bedrock fault,using Drucker-Prager Rule in Mohr-Coulomb theory. Under compressive stress silt soil is easier to deform than clay soil,while clay soil has more deformation under tensile stress and shear stress. In normal faulting of underlied bedrock fault, surface rupture in silt soil and clay soil have no obvious dissimilitude. In reverse faulting, the smaller the shear strength, the larger the dislocation for soil mass, and vice versa. That means silt soil is easier to deform than clay soil in reverse faulting.