Dynamic properties of concrete in direct tension

An experimental study on the strain-rate dependent behavior of concrete in tension was carried out by means of a servo-hydraulic testing machine. The specimens were made in dumbbell shape and the tested strain rate ranged from 10− 5/s to 10− 0.3/s. Strain-rate effects on the tensile strength, the modulus of elasticity, the critical strain, the Poisson's ratio and the energy absorption capacity of concrete were studied. More emphasis was placed on the influence of temperature and moisture content on the strain-rate sensitivity. All test data were analyzed, discussed and compared with available reference materials. In addition, strain-rate effects on the damage pattern of specimens were studied. It was observed that the fractured surfaces of the specimens became more and more flattened and a number of coarse aggregates were broken along the failure surfaces. Based on this phenomenon an explanation to the physical mechanisms of strain-rate enhancement during rapid loading was proposed.