Scheme for beam progressive collapse mitigation

Latest recommendations have made provisions to improve structure resistance to progressive collapse in the event of interior support collapse. This paper defines a mitigating scheme to repel progressive collapse in reinforced concrete beams due to damaged interior supporting member by providing a new path to transfer the loads to other supporting members. The mitigating scheme suggests the use of unbounded unstressed externally installed fibre reinforced plastic cables with straight profile and three deviators. An open source finite element package for structural analysis (ZEUS-NL) using the fibre element approach is adopted to numerically model the mitigated beam. The proposed numerical model evaluates the progressive collapse of such beams using a push-down analysis to simulate column removal. It assumes that the anchorage and deviator locations of the external cables act as rigid arms that connect the external cables to the beam. The numerical results demonstrate that the defined mitigating scheme increases the beam resistance to progressive collapse due to interior column failure.