A split Hopkinson pressure bar(SHPB)device in two-by-two form,including the bar bundle form and the single cylindrical bar form,was designed in response to the demand for the dynamic mechanical experiments for brittle...A split Hopkinson pressure bar(SHPB)device in two-by-two form,including the bar bundle form and the single cylindrical bar form,was designed in response to the demand for the dynamic mechanical experiments for brittle materials such as concrete,rock,etc.The stress waveforms generated through a projectile impacting two different types of incident bars have been studied based on the one-dimensional stress wave theory and numerical simulation method.At last,based on the established two types of mesoscale concrete models with random convex polyhedral aggregates,we performed comparison analysis of SHPB numerical simulations for concrete materials with bar bundle and single cylindrical bar separately,so as to provide technical support for the manufacture and development of this experimental device.The results showed that the introduced two-by-two form SHPB device expanded the scope of practical application,and the wave dispersion effect existing in a large-diameter bar can be evidently reduced when we employed the bar bundle form,indicating its applicability to the dynamic mechanical experiments of concrete-like heterogeneous materials.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51971188 and 51071134)the Science and Technology Major Project of Hunan Province(Grant No.2019GK1012)Huxiang High-Level Talent Gathering Program of Hunan Province-Innovative team(Grant No.2019RS1059).All these supports are acknowledged.
文摘A split Hopkinson pressure bar(SHPB)device in two-by-two form,including the bar bundle form and the single cylindrical bar form,was designed in response to the demand for the dynamic mechanical experiments for brittle materials such as concrete,rock,etc.The stress waveforms generated through a projectile impacting two different types of incident bars have been studied based on the one-dimensional stress wave theory and numerical simulation method.At last,based on the established two types of mesoscale concrete models with random convex polyhedral aggregates,we performed comparison analysis of SHPB numerical simulations for concrete materials with bar bundle and single cylindrical bar separately,so as to provide technical support for the manufacture and development of this experimental device.The results showed that the introduced two-by-two form SHPB device expanded the scope of practical application,and the wave dispersion effect existing in a large-diameter bar can be evidently reduced when we employed the bar bundle form,indicating its applicability to the dynamic mechanical experiments of concrete-like heterogeneous materials.
