Collapse Probability Assessment of a 4-Story RC Frame under Post-Earthquake Fire Scenario

Post-earthquake fire is a rare event with catastrophic consequences. The occurrence of fire after an earthquake can cause a catastrophe. Structural damage during earthquake loading affects the capacity of the element in the fire following earthquake loading. In this study, the probability of collapse and collapse time probability of a 4 story RC frame under earthquake and post-earthquake fire loading are assessed. At first structural sections are modeled in ABAQUS and heat transfer analysis is performed in them. After the results extraction of heat transfer analysis, the frame is modeled in openSees software base on the Finite Element method. For assessment seismic collapse probability, Incremental Dynamic Analysis (IDA) is conducted and the fragility curve is extracted for three performance levels. Then, seismic and fire loading are applied to frame consecutively and collapse probability is calculated. The probability distribution functions and the cumulative distribution function of the structural collapse time are calculated in the post-earthquake fire analysis. The results show that increasing PGA increases collapse probability and decrease collapse time in the RC frame under post-earthquake fire loading.