Thermal effects of steel-fibre-reinforced reactive powder concrete at elevated temperatures

Abstract

The focus of this work was the thermal properties (thermal conductivity, thermal diffusivity, specific heat capacity and linear expansion coefficient) of steel-fibre-reinforced reactive powder concrete (RPC) at elevated temperatures (20–900°C). The thermal properties of RPC, ordinary concrete and high-strength concrete were compared and analysed. The results showed that, with an increase in temperature, the thermal conductivity and thermal diffusivity first descended and then rose, while the linear expansion coefficient and specific heat capacity first increased and then decreased. By inputting the measured thermal parameters into finite-element software, the simulated temperature–time curves of RPC were obtained and compared with the measured curves. It was found that the two curves were basically consistent, so the measured thermal parameters were accurate and reliable and could be used in numerical simulation analysis of RPC structures under fire.