A coupled computational method for multi-solver, multi-domain transient problems in elastodynamics

This work presents an efficient and stable methodology for the coupling of Finite Element Methods (FEM) and Boundary Element Methods (BEM) that is independent of the particular solver and allows for independent temporal discretizations among solvers. The approach satisfies explicitly compatibility conditions and equilibrium of forces at the contact interfaces. Although the proposed approach has been developed in view of the soil–rail–vehicle dynamic interaction problem in High Speed Rail applications, it is expressed in a general form applicable to any multi-domain, multi-phase transient problem. The method development and formulations are presented in detail. Verification and application studies demonstrate the accuracy, efficiency and versatility of the method for the direct time domain solution of dynamic problems including structure–structure interaction and soil–structure interaction. The proposed approach demonstrates high accuracy and efficiency to that of direct coupling solutions and more rigorous methods.

► We developed a procedure for coupling multiple computational methods in elastodynamics.
► Independent time step selection is accommodated in each method.
► FEM, BEM and semi-analytic or closed form solutions are accommodated.
► The proposed technique does not require iterations.
► The proposed technique is highly accurate and stable.