Requirements of specimen dimension considering maximum coarse aggregate size for concrete split Hopkinson pressure bar tests

Dynamic increase factors (DIF) of concrete compressive strength have been proposed through experiments on specimens including small aggregates without considering the effect of the coarse aggregate size, which was due to the limitations in the size of specimens and test apparatus. Therefore, this study conducted an experimental investigation of the effect of the maximum coarse aggregate size (Gmax) on the DIF of normal-strength concrete. Split Hopkinson pressure bar (SHPB) tests were performed for mortar and concrete specimens with various sizes of Gmax, and the apparent and pure rate DIFs were obtained. Moreover, the pure rate DIF of each Gmax was verified through numerical analysis of the SHPB tests. The test and analysis results indicated that Gmax affected the dispersion of the apparent DIF and the values of the pure rate DIF. Based on these results, a guideline for the fabrication of specimens considering Gmax for concrete SHPB tests was suggested.

Automated summary

Dynamic increase factors (DIF) of concrete compressive strength have been proposed, but without considering the effect of coarse aggregate size. This study conducted experiments and numerical analysis to investigate the effect of maximum coarse aggregate size (Gmax) on DIF. The results showed that Gmax affected the dispersion of apparent DIF and values of pure rate DIF. Based on these findings, a guideline for fabricating specimens considering Gmax for concrete SHPB tests was suggested.