Investigation on thermophysical properties of reactive powder concrete

The thermophysical properties, such as thermal conductivity, thermal diffusivity, specific heat capacity and linear thermal expansion of reactive powder concrete (RPC) with different steel fiber volumetric fractions are investigated by means of high temperature tests. The thermophysical characteristics of RPC with different fiber volumes under different temperatures are analyzed and compared with those of the common high-strength concrete and high-performance concrete. The empirical relationships of thermophysical properties with temperature and fiber volume are identified. By the heat transfer and solid physics methods, the microscopic physical mechanism of heat transfer process and heat conduction properties of RPC are investigated, and the theoretical formulas of specific heat capacity and thermal expansion coefficient are derived, respectively. The effects of temperature and steel fibers on the specific heat capacity and the thermal expansion coefficient are quantitatively analyzed and the discriminant conditions are provided. It is shown that the experimental results are consistent with the theoretical prediction.