MCE Ph.D. Thesis Seminar

Abstract: FRAME3D, a program for the nonlinear implicit analysis of steel structures subjected to ground motion, has previously been used to study the collapse mechanisms of steel buildings up to 20 stories tall. The present thesis is inspired by the need to conduct similar analysis for much taller building structures. It improves FRAME3D in two primary ways. First, FRAME3D's ability to track earthquake-induced building collapse is made more robust. Second, a parallel FRAME3D (PFRAME3D) is developed. The serial code is optimized then parallelized. A distributed-memory divide-and-conquer approach is used for both the global direct solver and element-state updates. The result is an implicit finite-element hybrid-parallel program that takes advantage of the narrow-band nature of very tall buildings and uses nearest-neighbor-only communication patterns. Maximum speedups attained with this parallel framework increase with building height. PFRAME3D is used to analyze a hypothetical 60-story steel moment-frame tube building. Dynamic pushover and time-history analyses are conducted, and multi-story shear-band collapse mechanisms are observed.