Progressive collapse evaluation of RC frames under high-temperature conditions : experimental and finite element investigations

In this paper, the behavior of a four-bay three-storey two-dimensional RC frame is experimentally investigated under high-temperature with 50% working load conditions in stable and transient states. One-fifth scale model is used for experimental investigation. The finite element model has also been developed with a reduced scale of 1/5th ratio of the prototype model. The high-temperature oven is used for heating the critical column in the RC bare frame and infilled frame with the capacity of 1000 °C. The temperature was monitored using a thermocouple at the middle of the cross-section in the column. In transient state analysis, the bare frame expansion occurs at the middle column as 2.32 mm vertically, and for the infilled frame has been 1.02 mm. The failure happens after the expansion by cause of high temperature with 50% working load as 15.75 mm in the bare frame and 1.42 mm for the infilled frame at the third storey level. It was observed that in the case of the infilled frame, the amount of vertical displacement in the middle column is reduced to 90.98% compared to the bare frame.