An open-source ABAQUS UEL implementation of SBPML for wave problems

Abstract

In the numerical simulation of wave problems, it is often necessary to truncate the unbounded computational domain at a finite distance to reduce the requirement of computational resources. To manage this truncation, artificial boundaries are introduced, among which the Scaled Boundary Perfectly Matched Layer (SBPML) is regarded as a reliable strategy. In this paper, we implement the SBPML element into the commercial software ABAQUS using the User-Defined Elements (UEL) subroutine. The key equations of the SBPML, the procedures of meshing for the SBPML domain, and the implementation workflow of the subroutine are given in details. Four benchmark examples of wave propagation problems in unbounded domains are presented to demonstrate the accuracy and effectiveness of the proposed method. Furthermore, the application of the UEL in nonlinear seismic soil-structure interaction analysis is demonstrated by evaluating the seismic response of a five-layer alluvial basin in a homogeneous half space and an aboveground-underground integrated structure-multilayer soil system under obliquely incident earthquake waves. Using the proposed UEL, all wave propagation analyses can be directly implemented in ABAQUS with a seamless workflow. To facilitate the use of the proposed approach, the codes of the UEL are published in an open-source format.