Progressive collapse of RC frame structures after a centre column loss
The progressive collapse of a reinforced concrete (RC) frame structure due to the loss of a centre column was investigated in a static experimental study. A two span, two bay, single storey one third scale model representing a segment of a larger space frame structure was tested. Downward displacement of the top of the removed centre column was imposed until failure, and frame collapse was defined as the rupture of tension steel bars in the floor beams. The study provides insight into the behaviour and failure modes of the structure under centre column loss, including the development of catenary action in the frame beams and tensile membrane action in the frame slabs. The experimental observations and theoretical analysis were used to establish a simplified calculation model of the resistance capacity of RC frame structures against progressive collapse due to the loss of a centre column. The reliability of the proposed model was verified using experimental results.