Probabilistic Approach to Progressive Collapse Prevention. Physics Based Simulations

Physics based collapse simulations of moment resisting steel framed buildings are presented. Survival probability of a building occupant is proposed as a single scalar measure to quantify resistance to progressive collapse of a particular structure at hand. Practical procedure for the survival probability calculations by means of physics based simulations and theorem of total probability is shown in the paper. Simulations of structural response to the sudden removal of a key structural member have been carried out for a number of failure scenarios. Such analysis is at the forefront of civil engineering modeling because it involves material nonlinearities, large deflections, finite strains, and certainly requires dynamic analysis. Saving human lives in the case of abnormal loadings and/or unexpected hazards is equivalent to minimizing the area of collapsed floors. Such approach should also minimize the financial loss to a building owner. The area of collapsed floors can be extracted from the physics based simulations. It is proposed to quantify the goodness of design with the survival probability of a building occupant. Such single scalar measure provides an opportunity to employ optimization algorithms to produce the safest and the most economic structural design.