Dynamic Compressive Performance of Concrete Exposed to High Temperature Based on Microstructure Analysis

Combined with strain gauge measurement method, the modified split Hopkinson pressure bar was adopted to investigate the behavior of normal concrete and steel fiber reinforcement concrete exposed to 400°C and 800°C under axial impact compressive loading. The experimental results show that compared with normal temperature, the compressive strength and elasticity modulus of normal concrete exposed to 400°C and 800°C decrease obviously. The transformation of concrete exposed to high temperature in microstructure is analyzed by SEM. The influence of high temperature on macro mechanics performance is discussed.