Progressive collapse capacity analysis of reinforced concrete frame structures considering catenary action

The effects of catenary action on reinforced concrete (RC) frame structures to resist progressive collapse were investigated. An OpenSees-based macro-model considering the catenary action was developed. The macro-model was validated by comparing the simulated results with the test results of two RC beam-column substructures, which were subjected to the loss of a middle column scenario. Moreover, the effects of catenary action on the response of a ten-story RC frame structure to resist progressive collapse were examined by both nonlinear static and nonlinear dynamic analyses from the alternative path method. The results show that if ignoring the catenary action, the progressive collapse capacity of RC frame structures will be underestimated. When the catenary action is not considered, the calculated maximum load increase factor for the frame subjected to the loss of the middle column of the first story is less than 2.0, while it is beyond 2.0 with considering the catenary action.