粗骨料种类对刚性弹贯穿混凝土靶剩余速度的影响

摘要

On projectile perforating concrete targets,a concrete mesoscale model can be used to describe the effect of various mediums on concrete mechanical properties.Algorithms for forming and distributing random 3 D spherical coarse aggregate were proposed.A 3D finite element mesoscale concrete model consisting of mortar matrix and coarse aggregate was established based on the theory of background element and material identification.The interfacial transition zone was simplified as a kind of contact between elements.Based on this model,a continuous finite element code was used to simulate the process of rigid-projectiles perforating concrete targets and the effects of 3 different coarse aggregates on residual velocities were analyzed.The results indicated that the strength and density of coarse aggregate affect the residual velocity under lower and higher impact velocities,respectively.%针对弹体贯穿混凝土靶问题，混凝土细观尺度模型能够反映混凝土中各介质对混凝土力学行为的影响。本研究编写了三维随机球形粗骨料的生成和投放程序，并采用一种基于背景网格的材料识别技术建立了含有水泥砂浆和粗骨料两种网格的三维混凝土细观有限元模型，同时将界面过渡区简化为这两种网格之间的一种可失效的接触。基于这一模型，运用连续有限元软件对刚性弹贯穿混凝土过程进行了数值仿真，并分析了三个不同种类的粗骨料对剩余速度的影响。结果表明，粗骨料的强度和密度分别在较低和较高的着靶速度下对剩余速度有一定影响。