AN APPROACH TO NUMERICAL SIMULATION FOR EXTERNAL SOURCE WAVE MOTION

The wave field of artificial boundary is separated into free field without local topography effect and scattering field induced by local topography effect. In infinite ground, the influence of wave propagation on artificial boundary is realized by transforming displacement field as well as velocity field to stress field which are imposed on the boundary nodes, and scattering wave field is modeled as a far field approximately solution introduced by Du Xiuli. On this basis, the time domain numerical simulation of local topography effect under obliquely incident transient plane wave can be performed in virtue of general FEM software. Thusly, an efficient method to calculate external source wave motion such as local topography effect in two or three dimension irregular, uneven field and soil structure dynamic interaction is developed. The advantage of the proposed method will simplify the analysis of nearfield wave with strong solver and pre-post process of general finite element software. In fact, due to the strong calculation function of general FEM software, the method can easily applied to the analysis of uneven and nonlinear problems.