Effects of Temperature and Strain-Rate on the Compressive Strength of Concrete

Dynamic compressive tests were carried out for concrete specimens after exposure to temperatures 23°C, 400°C, 600°C and 800°C by using Split Hopkinson Pressure Bar(SHPB) apparatus. Cylindrical specimens with 98mm in diameter and 49mm in length were used in tests. The strain rates achieved in tests ranged from 30s-1 to 220s-1. The results showed that the compressive strength increases with increasing strain-rate, but decreases with the increase of temperature. However, the effect of strain-rate on improving the compressive strength of concrete decreases with the increase of temperature. Moreover, the strain-rate has an improvement on the peak strain of concrete, and the accretion rate increases with increasing temperature.