Experimental study on thermal parameter of reactive powder concrete

Using hot wire method, experiments on the thermal conductivity coefficient of 230 mm×165 mm×65 mm reactive powder concrete (RPC) test specimens with four different fiber volumes (RPC without fiber, RPC with polypropylene fiber volume content of 0.2%, RPC with steel fiber volume content of 2% and RPC with volume content 0.2% polypropylene fiber and 2% steel fiber) were made in the temperature of room temperature, 100℃, 200℃, 300℃, 400℃, 500℃, 600℃, 700℃, 800℃ and 900℃. Research on the thermal conductivity of RPC influenced by temperature, fiber types and fiber volumes has been carried out. The formula reflecting the increase of RPC thermal conductivity with the increase of temperature was fitted. The thermal conductivity coefficient of RPC was compared with high strength concrete and normal concrete. The results show that the thermal conductivity coefficient of RPC is higher than high strength concrete and normal concrete. The inversion test on different fiber volumes in RPC in high temperature was completed, including the measurement of the center temperature of specimens in stove. Combined with the measured values of thermal conductivity of RPC and the temperature curve of specimen center, the simulation of temperature field of RPC specimens in the high temperature was made using the software ABAQUS, and their specific heat capacity was further obtained by inversion. The establishment of the calculation formula for the specific heat capacity of RPC was completed, showing that the constant specific heat capacity is a constant from room temperature to 100℃ and from 600℃ to 900℃, while increases with the increase of temperature from 100℃ to 600℃.