基于不同材料模型的混凝土SHPB试验数值模拟

发布时间：2018-07-26 14:00

【摘要】：为了分析不同材料模型对混凝土分离式霍普金森压杆(SHPB)试验数值模拟结果的影响,在LS-DYNA软件中分别运用KC,HJC,CSC三种材料模型对混凝土的SHPB试验进行模拟.利用脉冲整形器对入射波进行整形以减小弥散效应,实现恒应变率加载,并从SHPB试验的基本假定出发验证了有限元模型的准确性.通过数值模拟得到了不同撞击速度下基于3种材料模型的混凝土破坏过程及其应力-应变曲线.结果表明:KC,HJC,CSC三种模型基本上能够反映混凝土的动态力学特性,且KC模型和CSC模型的失效模式为核心塌陷,而HJC模型则表现出留核现象;在相同的平均应变率下,HJC模型和KC模型的动力放大系数大于CSC模型;随着平均应变率的增加,峰值应变增大,CSC模型和HJC模型的割线刚度减小,而KC模型的割线刚度变化不明显.
[Abstract]:In order to analyze the influence of different material models on the numerical simulation results of concrete split Hopkinson compression bar (SHPB) test, the SHPB test of concrete was simulated by using three kinds of material models in LS-DYNA software. The pulse shaper is used to shape the incident wave to reduce the dispersion effect and to realize the constant strain rate loading. The accuracy of the finite element model is verified by the basic assumption of the SHPB test. The failure process and stress-strain curves of concrete under different impact velocities are obtained by numerical simulation. The results show that the three kinds of models can basically reflect the dynamic mechanical properties of concrete, and the failure modes of KC model and CSC model are the core collapse, while the HJC model shows the phenomenon of core retention. At the same average strain rate, the dynamic magnification factor of HJC model and KC model is larger than that of CSC model, and with the increase of average strain rate, the Secant stiffness of CSC model and HJC model decreases with the increase of average strain rate, but the change of Secant stiffness of KC model is not obvious.
【作者单位】：东南大学土木工程学院;
【基金】：国家自然科学基金资助项目(51678141) 江苏高校优势学科建设工程资助项目(CE02-2-20) 江苏省普通高校研究生科研创新计划资助项目(KYLX16_0259)
【分类号】：TU528

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