ملخص: This paper describes the numerical simulation of the far field problems with loads having non-vanishing time average encountered in some dynamic problems, such as the foundation for a transmission line tower when the cables on one side snap and pile driving analysis, by using the modified generalized Smith boundary. This is obtained by the simplification of the boundary conditions of the generalized Smith boundary, by performing the reinitiating and update process of the constant velocities and constant stress conditions for each time step through only one layer of finite elements. The theory is simplified, hence allowing a substantial gain in memory space and also machine time. Furthermore, the spurious reflections are cancelled for each time step calculation. This transmitting boundary is implemented with a mixed time marching algorithm, i.e. implicit/explicit for the interior domain and explicit for the boundary nodes, and its performance is verified for loads having non-vanishing time average. Obtained results are compared to the viscous boundary and the algorithm of extrapolation solutions, and are found satisfactory as the curves for two-dimensional problems oscillate continuously around the static value, leading thus to a reliable simulation of this kind of loading.

لغة: إنجليزية