Modelling the catenary effect in the progressive collapse analysis of concrete structures

Progressive collapse is a phenomenon in which local failure of a structural component due to a gas explosion or blast may lead to failure of the entire structure or a significant part of it. RC structures can resist progressive collapse through various mechanisms such as frame action and catenary action.
In this paper, the effect of catenary action on the resistance of concrete frame structures to progressive collapse is modelled using limit analysis. Non-linear optimization is performed for this. It is observed that although frame action is known to be the main mechanism resisting progressive collapse, at the end of this action, after rupture of bottom bars, catenary effects may bring about a noticeable increase in the resistance of the structure. The results show good agreement with the experimental results of other researchers.