Title: Sidesway Collapse of Deteriorating Structural Systems Under Seismic Excitations (NEES-2005-0084)
Year Of Curation: 2011
Description: Understanding, predicting, and preventing collapse have always been major objectives of earthquake engineering. Collapse is the main source of injuries and loss of lives. Thus, it constitutes an engineering limit state that needs to be predicted in order to evaluate, in a probabilistic format, the life safety performance level, which is of primary societal concern. In the context of earthquake risk management, a process is needed that permits a rigorous assessment of the probability of collapse to make informed decisions in the best interest of society. In the context of earthquake resistant design, this process needs to be simplified so that the engineering profession can use engineering techniques, which are based on parameters such as strength, stiffness, and ductility (deformability), to derive structural properties that comply with specified targets for a required level of collapse safety, or a tolerable probability of collapse.This project will address both contexts. It will provide a methodology and reliable data for predicting a critical mode of collapse, namely that associated with sidesway instability in which an individual story (or a series of stories) displaces sufficiently so that the second order P-delta effects fully offset the first order story shear resistance and dynamic instability occurs, i.e., the structural system loses its gravity load resistance. Prediction of this mode of collapse is a challenging problem because structural components will deteriorate in strength and stiffness before the collapse limit state is reached, and great uncertainties are associated with the description of the seismic input and of the parameters that control the response of structures close to collapse.The methodology will be based on a combination of analytical and experimental simulations, with the former being carried out at Stanford University and the main effort of the latter, two shaking table collapse tests of a model of a steel structure, being carried out at the NEES facility at the University at Buffalo.
PIs & CoPIs: Helmut Krawinkler, Andrew Whittaker
Dates: September 01, 2005 - March 26, 2009
Organizations: California Geological Survey, Stanford University, CA, United States, State University of New York at Buffalo, NY, United States
Facilities: Stanford University, CA, United States,State University of New York at Buffalo, NY, United States
Sponsor: NSF - 0421551
Keywords: Steel Structure,Simulation,Structural Stability,Steel Framed Buildings,Shaking Table Test,Steel Moment-Resisting Frames
Publications: "Sidesway Collapse of Deteriorating Structural Systems Under Seismic Excitations"