Experimental investigation of fire effects on ductility and stiffness of reinforced reactive powder concrete columns under axial compression

Abstract

This study is an experimental investigation into the performance of reactive powder concrete (RPC) columns after fire exposure. The study aims to give a comprehensive account of the fire effects on ductility, energy absorption capacity and stiffness characteristics of twelve 100 × 100 × 900 mm RPC columns subjected to axial load, and to investigate the effect of introducing lateral ties and increasing concrete cover on improving post-fire behaviour of these columns with respect to ductility, energy absorption capacity and stiffness characteristics. The obtained results showed that it is more suitable to determine the energy absorption capacity than using displacement ductility index for assessment the ductility situation of RPC columns after being exposed to fire. Furthermore, high reduction in initial and secant stiffness of RPC columns was observed after fire exposure and the percentages of reduction are higher with increasing fire temperature from (400 to 600 °C).