Dynamic visualization and wave propagation by viscoelastic impact

进行了高速和低速冲击试验，研究了琼脂、凝胶、颗粒物等软物质的流变特性。对于琼脂凝胶，一个钢球被扔到了它上面。我们开发了一种通过琼脂凝胶对冲击响应的图像分析来估计粘弹性性质的方法。虽然所开发的方法存在一些局限性，但我们可以使用所开发的方法来估计其流变性。对于颗粒状物质，我们进行了低速撞击(穿透)实验。在侵彻过程中，测量了声发射信号。利用声发射方法，可以检测出颗粒网络的单个倾斜或重排。我们发现声发射事件的分布服从幂规律。并将幂指数与地震分布进行了比较。

High-speed and low-speed impact experiments were performed to study the rheological properties of various soft matters such as agar gel and granular matter. For agar gel, a steel ball was dropped to it. We developed a way to estimate the viscoelastic properties from the image analysis of the agar gel response to the impact. While the developed method has several limitations in it, we can estimate the rheological properties by using the developed method. For granular matter, we carried out the low-speed impact (penetration) experiments. During the penetration, AE (Acoustic emission) signals were measured. By the AE method, the individual slop or rearrangement of grains network can be detected. We found that the AE events distribution obeys power law. The power law exponent was compared with the Earthquake distribution.