Most investigations on progressive collapse analysis of structures subjected to extreme actions cannot modify analytical model according to real-time damage evolution status

and various impact processes caused by failed structural components during progressive collapse cannot be considered as well. Such issues associated with impact are truly crucial in numerically predicting structural responses during progressive collapse analysis. According to the beam-to-beam impact mechanism developed for reinforced concrete frame structures

impact force-time history is determined by using Matlab language and then is incorporated into OpenSees platform to modify structural model. The effect of beam-to-beam impact behavior on the responses of RC concrete frame structures excited by strong earthquakes can be reasonably reflected. The results of these procedures are compared with those from conventional time history analysis for an example RC frame. It can be concluded that the incorporation of Matlab and OpenSees Tcl language can compute impact force time history and modify structural model in real-time. With the consideration of beam-to-beam impact and progressive failure of components

the horizontal displacement and rotation of the structure increase while the vertical displacement decreases to some extent.