*Hesheng Bao
Computational Mechanics Laboratory, Department of Civil and Environmental Engineering
Carnegie Mellon University
Pittsburgh, PA 15213*

Computational Mechanics Laboratory, Department of Civil and Environmental Engineering

Carnegie Mellon University

Pittsburgh, PA 15213

Computational Mechanics Laboratory, Department of Civil and Environmental Engineering

Carnegie Mellon University

Pittsburgh, PA 15213

Computational Mechanics Laboratory, Department of Civil and Environmental Engineering

Carnegie Mellon University

Pittsburgh, PA 15213

School of Computer Science

Carnegie Mellon University

Pittsburgh, PA 15213

School of Computer Science

Carnegie Mellon University

Pittsburgh, PA 15213

Computational Mechanics Laboratory, Department of Civil and Environmental Engineering

Carnegie Mellon University

Pittsburgh, PA 15213

**Abstract.** We describe the design and discuss the
performance of a parallel elastic wave propagation simulator that is
being used to model earthquake-induced ground motion in large
sedimentary basins. The components of the system include mesh
generators, a mesh partitioner, a parceler, and a parallel code
generator, as well as parallel numerical methods for applying seismic
forces, incorporating absorbing boundaries, and solving the
discretized wave propagation problem. We discuss performance on the
Cray T3D for unstructured mesh wave propagation problems of up to 77
million tetrahedra. By paying careful attention to each step of the
process, we obtain excellent performance despite the highly irregular
structure of the problem. The mesh generator, partitioner, parceler,
and code generator collectively form an integrated toolset called
Archimedes, which automates the solution of unstructured mesh PDE
problems on parallel computers, and is being used for other
unstructured mesh applications beyond ground motion modeling.

**Keywords.** absorbing boundaries, computational
geometry, finite element methods, local site effects, mesh generation,
parallel unstructured PDE solvers, parallelizing compilers, seismic
wave propagation, strong ground motion.

- Introduction
- Numerical approximation issues
- Algorithms
- Archimedes: A system for unstructured PDE problems on parallel computers
- Performance on the Cray T3D
- Concluding remarks
- Acknowledgments
- References
- About this document ...

Mon Aug 5 00:59:45 EDT 1996