Progressive collapse analysis of RC frames subjected to blast loading

Progressive collapse of a building can be triggered by damage to certain critical load-carrying elements immediately following a blast. The initial damage can be followed by a chain of events which progressively destabilize the building. The modelling of progressive collapse is very complex and must take into account the nature and extent of damage inflicted to the individual elements, the behaviour resulted from the damage and the structural interaction between the elements. Importantly, the chain of events to be modelled is dynamic in nature. This paper critically compares some analysis methods available for progressive collapse design from the very simple linear elastic static analysis to the most rigorous and time consuming nonlinear dynamic analysis which takes into accounts both the primary and secondary effects of the blast loading. Inelastic non-linear dynamic finite element analyses and computational fluid dynamics have been employed in the evaluation which revealed certain deficiencies with the simplified methods including the non-linear dynamic analysis method which does not take into account the direct impact of the blast loading.