Development of An Analytical Database to Support a Fast Running Progressive Collapse Assessment Tool

Rapid assessment of structures for vulnerability to progressive collapse has become a major concern in today’s world environment. Homeland Security and Overseas U. S. government agencies need the ability to quickly, and realistically, evaluate buildings to determine the risk of progressive collapse and understand how proposed retrofits would improve the building risk. To support the development of a fast running assessment tool, a series of simplified finite element simulations were conducted to generate a response data base. Models of simplified concrete and steel frames were run under gravity collapse conditions to determine displacements, forces and moments transmitted to adjacent structural members. The simulations were performed using Weidlinger Associates’ FLEX finite element code. This paper will discuss the salient issues involved in the nonlinear, dynamic modeling of progressive collapse. The FLEX modeling used to develop the data base and confirm expected response is also described in detail. Finally, the simplified analytical tool that was developed from the simulation data base development effort will be described.