Electromagnetic Gage Techniques for Dynamic Tensile Fracture

年轻 硬岩开挖受动态拉伸断裂控制， 是一个人们知之甚少的过程。 关于动态的现有数据 脆性材料如岩石和陶瓷的抗拉强度 非常有限，可用的数据是开放的问题，因为它 通过表面测量获得，其中表面FLWS可能具有 对断裂性能的影响。 这项研究计划涉及 动态抗拉强度的测量 在测试样本的内部。 具体而言，该研究计划需要开发一个 一种能感应粒子的小尺寸电磁规 可以与所施加的动态应力相关的速度。 盖奇 标本中的放置技术将是 项目 数据将被数字化记录和处理 自动给出速度、位移和应力的函数 在动态断裂过程中的时间。 该办法将 动态抗拉强度和/或韧性将被证明， 测定几种脆性岩石、塑料、复合材料和陶瓷。 朝阳恢复是一个小公司与一个优秀的实验室， 进行这个实验项目。 首席研究员有一个 在岩石力学优秀的背景，并已显示的可行性， 电磁传感器在岩土工程中的应用 材料. 建议给予奖励。

YOUNG Excavation of hard rock is controlled by dynamic tensile fracture which is a process that is poorly understood. Available data on the dynamic tensile strength of brittle materials such as rocks and ceramics is extremely limited, and the data available is open to question because it is obtained by surface measurements where surface flws may have an influence on the fracture properties. This research program involves the measurement of dynamic tensile strength with an embedded gage placed in the interior of the test specimen. Specifically, the research program entails the development of an electromagnetic gage of small dimension which will sense particle velocities which can be related to the imposed dynamic stresses. Gage placment techniques in the specimen will be an important part of the project. The data will be recorded digitally and processed automaticallly to give velocity, displacement and stress as a function of time during the dynamic fracture process. The method will be demonstrated and dynamic tensile strength and/or toughness will be determined for several brittle rocks, plastics, composites and ceramics. Sunburst Recovery is a small company with an excellent laboratory for conducting this experimental program. The principal investigator has an excellent background in rock mechanics and has shown the feasibility of using electromagnetic transducers in measuring properties of geo- materials. An award is recommended.