High-performance dynamic solid-fluid coupled simulation method for geotechnical engineering

Research on mega scale geotechnical engineering projects has raised new challenges of computational capability. In order to study the static and dynamic response of complex structures in saturated soil, it is essential to develop high-performance computing methods for solid-fluid coupled analysis. This study proposes a finite element method-finite volume method (FEM-FVM) coupled framework for parallel solution of solid-fluid coupling problems, and Fully Implicit Coupled Method (FICM), Fully Explicit Coupled Method (FECM), and Solid Explicit Fluid Implicit Method (SEFIM) are developed. A comparative analysis of these methods in terms of accuracy, single core efficiency, stability, and parallel performance is conducted, providing theoretical support and practical guidance for appropriate method selection. Regarding accuracy, the study analyzes the excess pore water pressure time-history obtained by different methods for a Terzaghi one-dimensional consolidation problem, all three methods are qualified. In terms of single core efficiency, the study shows that for small scale problems, FICM is more suited for static problems, whereas FECM and SEFIM are more suitable for dynamic problems. Regarding parallel computing performance, the analysis of scalability and speedup indicates that FECM and SEFIM have significant advantages over the fully implicit method when solving large scale problems over 10 million degrees-of-freedom. Especially, the explicit FECM can achieve high scalability for problems with over 100 million degrees-of-freedom.