Dynamic compressive and splitting tensile tests on mortar using split Hopkinson pressure bar technique

Abstract

Dynamic compressive and tensile properties of mortar under impact loading were investigated experimentally by using a split Hopkinson pressure bar (SHPB) apparatus with pulse shaping technique. Firstly, the basic principle, experimental limitations and some feasible improvements/modifications of SHPB technique used for dynamic tests on concrete-like materials were summarized briefly. And then the dynamic compressive strength, stress versus strain response, and failure modes of mortar were discussed and analyzed. Finally, a dynamic Brazilian disc test was conducted to obtain the splitting tensile property of mortar, and some typical experimental results were presented. Both compressive and splitting tensile results show that mortar is a strain-rate sensitive material. Either compressive or tensile strength enhances with the increase of strain rate, especially when the strain rate is greater than the transition strain rate, which is around 20 s-1 for the dynamic compression and 2.0 s-1 for the splitting tension, respectively. These findings are helpful to guide the design and application of concrete structures.