Design of Reinforced Concrete Frame Structures to Resist Progressive Collapse under Blast Loading

Following the provision addressed in "Design of Structure to Resist Progressive Collapse" ( UFC 4 -023 -03), including the removal locations of vertical load-bearing elements, loads combination, failure criteria for structural elements and damage limits of RC structures, a design study on reinforced concrete frame structures to resist progressive collapse under blast loading was carried out by using alternate path method. The structure was originally designed in accordance with the current Chinese design code. The full load-deformation development of plastic hinges for flexural and compressive-flexural members was also considered by using fiber model. It was found that the originally designed structure can not meet the design requirements to resist progressive collapse. Then a parameter study was conducted to understand the influence of some factors on the structural performance to resist progressive collapse. Results indicate that it significantly improves the performance of RC frame structure to resist progressive collapse to reduce the column span, while it has indistinctively effect to enhance the seismic fortification criterion and the capacity of a structure to resist progressive collapse will be weakened by increasing the stories of the structure. Finally three design schemes for the building to resist progressive collapse were proposed with a brief economic comparison, among which the design scheme to increase the redundancy of the structure and the bearing capacity of structural members simultaneously is the optimum plan.