Study and Evaluation of Biological Threat of Cotton Bollworm in the West and Central Part of the Golestan Province Using Molecular Method

One of the important issues in passive defense considerations is progressive collapse. Progressive collapse of the structure occurs when the major structural load carrying members are removed suddenly and the remaining structural elements are not capable of supporting the weight of the building and eventually result in collapse and failure of the structure. The main purpose of this investigation is assessment of the progressive collapse capacity of reinforced concrete special moment frame that is designed according to Iranian National Building Code (part 9). In this paper, two methods of analysis, nonlinear static analysis (pushdown analysis) and linear static analysis, are used for evaluating the progressive collapse capacity of special moment resisting frames with 3, 5 and 7 stories under two different scenarios. The Progressive collapse potential of SMRFs is evaluated based on the acceptance criteria of the last edition of UFC 4-023-03 document. The results show that the linear static analysis procedure has more conservative results compared to the pushdown analysis and the beam elements are also more vulnerable to progressive collapse than column elements.