A New Method for Developing Seismic Collapse Fragility Curves Grounded on State-Based Philosophy

Abstract

Since the current process to achieve the collapse fragility curve in practical applications seems too complicated, also time-consuming to dominant by structure designers, the focus of this study is on introducing of a new approach for establishing collapse fragility curves which requires less analytical effort. To achieve this goal, state-based philosophy (SBP) has been taken into consideration. This theory benefits from some similarities in the nature of every failure process in solid mechanics regardless of its source. In this study these similarities are used intelligently in procedure of formulating new fragility function which has couple of unknown parameters. Next, it will be shown that these parameters can be attained from two different sources: the pushover curves of the structure, some selective damage data from incremental dynamic analysis analyses. Finally a complete form of new collapse fragility function which is called "SBP fragility function" proposed as a substitute for conventional collapse fragility function. The most important advantage of this new fragility function is its non-probabilistic structure that will make a huge difference in the amount of effort required to achieve the fragility curves. In this research, in order to ensure the efficiency, accuracy of this fragility function all steps of SBP fragility analyses are done on some special moment frames models, their results are presented.