双节点有限元模拟直立走滑断裂地震位移场

Modeling of Asymmetric Earthquake Displacement Field of Vertical Strike-slip Fault by Using Double-node Finite Element Technique

结合位错理论和有限单元法,对介质横向不均匀性引起的直立走滑断裂地震水平位移场不对称性进行了数值模拟研究。结果表明,断层两侧介质泊松比和弹性模量的横向不均匀性,均可以引起直立走滑断层同震破裂及地震位移场的不对称性,其中,断层两侧介质的剪切模量比(刚度比)对直立走滑断裂地震位移场不对称性起主要作用。

Using the Finite Element Method (FEM) and dislocation theory, we simulated the asymmetric earthquake displacement field of a vertical strike-slip fault caused by laterally inhomogeneous medium. The result reveals that the lateral heterogeneities of Poisson’ratio and elastic module can both lead to asymmetric horizontal displacement field and asymmetric rupture of a vertical strike-slip fault, and the shear modulus ratios (stiffness ratios) of both sides of the fault play a key role in the characteristics of asymmetry.