In order to investigate the dynamic compressive behavior of a concrete material, tests on its specimens with rough aggregates of diameter from 15 mm to 20mm were performed under compressive impact loading using SHPB (Φ100 mm) (split Hopkinson pressure bar) apparatus, and the average strain-rate in the tests was in the range of 30 s-1to 180 s -1, the photographs related to the deformation or the failure process of the concrete specimens under dynamic compressure were obtained as well. Results showed that once the stresses in the specimens grow up to a value nearby the peak one, a macro-crack along the axes of the concrete specimens can firstly be observed on its surface, but its failure are finally related to development and expansion of the primary multi-macro-crack along the axes of the specimens; a modified ZWT concrete constitutive model is proposed, the results predicted with it are in good agreement with those of tests.%为研究混凝土材料的动态性能,利用直径φ100 mm的SHPB(Split Hopkinson Pressure Bar)装置对骨料尺寸为15 mm～20 mm的混凝土材料试样进行了应变率范围30s(-1)～180s(-1)的动态压缩试验,并借助高速摄影装置获得了试样的变形与破坏过程,结果表明:在动态压缩强度附近应力区,材料表面先出现一条沿试样轴向的可见宏观裂纹,而多条主裂纹的形成与扩展才导致材料的最终破坏;建立了改进的ZWT模型,模型预测结果与试验结果较吻合.
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