Experimental Study on Dynamic Behavior of Concrete at Elevated Temperatures

A split Hopkinson pressure bar (SHPB) was used experimentally to investigate the dynamic behavior of concrete at elevated temperatures. After the cylinder concrete specimens were heated to a pre-determined temperature by a purpose-developed electrical furnace, they were impacted by the SHPB bars to failure. The stress and strain time history curves of the tested specimens were recorded to analyze the impact behavior of concrete at elevated temperatures. The effects of high temperature and impact velocity on the dynamic strength and stress versus strain relationships of concrete were discussed. Generally, the dynamic strength of concrete at elevated temperatures decreased while the compressive deformation increased remarkably with the increase of temperature. Concrete at elevated temperatures tended to be more strain-rate sensitive under impact loading with the increase of high temperature except that at temperature of 200 degrees C. The dynamic behavior of concrete at temperature of 200 degrees C was obviously different from that of concrete specimens at room temperature and at elevated temperatures higher than 200 degrees C. Therefore, much attention should be paid to no dynamic effect of concrete at temperature of 200 degrees C.