Engineering Research Equipment Grant: Multiple Spark-Gap Camera

提供了用于配置具有大约每秒一百万帧的成帧速率的多火花间隙相机的研究设备。此次收购将补充现有的爆炸液化实验室和现场，目前在那里进行饱和土壤中的小规模爆炸加载现场测试。使用多火花隙相机进行的研究将允许进行实验室测试，以研究土壤的非饱和和饱和光弹性模型的弹性动力学行为。土壤颗粒被模拟为一系列大小不同的圆形和随机形状的圆盘。这种类型的建模提供有关波速、接触应力(法向和切向)以及粒子之间接触持续时间的基本信息。这些都是严格分析以非线性应力-应变行为为准则的复杂动力波-土相互作用所必需的信息，为适应饱和土壤的实验模型提供了可能性。多火花隙相机还有望展示一种新概念的实用性，即亚表面波GIDE，用于将结构与表面振动隔离。这是一个概念，它可以为使用壕沟和其他表面波导波提供一种替代方案，这些在现实世界中的应用在大多数情况下是不切实际的。

Research equipment is provided for the configuration of a multiple spark-gap camera having framing rates of about one million frames per second. Its purchase will complement an existing blast-induced liquefaction laboratory and field site, where small-scale, blast- loading field tests in saturated soils are currently performed. Research conducted with the multiple spark-gap camera will permit laboratory tests to be conducted to study the elasto-dynamic behavior of unsaturated and saturated photoelastic models of soils. The soil particles are modeled as a series of round and randomly shaped discs of different sizes. This type of modeling provides basic information about wave velocities, contact stresses (normal and tangential) and contact duration between particles. This is all necessary information for a rigorous analysis of the complex dynamic wave-soil interaction where nonlinear stress-strain behavior is the norm, providing the potential for adaptation to experimental modeling of saturated soils. The multiple spark-gap camera is also expected to show the usefulness of a new concept, that of the subsurface wave gide, to isolate structures form surface vibrations. This is a concept which may provide an alternative to the use of trenches and other surface wave guides, which for the most part are impractical in real world applications.