混凝土材料动态力学性能实验与数值模拟研究

Experiments and Numerical Simulations of Concrete Dynamic Mechanical Properties

利用轻气炮对素混凝土材料进行了3种不同冲击速度下的动态力学性能实验,得到了时间-应力曲线,随后利用软件进行数值模拟,将模拟结果与实验结果进行比较,解释了飞片和靶板破坏过程中波的传播过程。通过分析发现:混凝土材料表现出明显的率相关性、滞后效应和应力波的衰减特征,这些与材料内部损伤的演化密切相关;混凝土材料在压缩波、边侧稀疏效应和左、右自由表面反射拉伸波的共同作用下,最终形成宏观破碎;实验中靶板尺寸设计合理,有效避免了边侧稀疏效应对锰铜压阻计测试信号的影响。

A light gas gun was used to conduct the dynamic mechanical properties experiments of plain concrete material under three different impact velocities, getting the time-stress curves. Then, numerical calculations were used to simulate concrete＇s light gas gun experiments, comparing the simulation results with experimental results. In this paper the propagation of wave in flyer and target was formulated. Further analysis shows that concrete material has obvious rate-related properties, lag effect and stress wave＇s attenuation features, and all of this is closely related to the evolution of internal damage in material. Concrete material finally forms macro fracture under the interaction of compression wave, Side release effect and reflected tensile wave of left and right free surface. The size of target in the experiment is reasonable, avoiding the effect of side releasing on the test signals of manganin piezoresistive transducer.