Development of Cuttability Criteria for Rocks

岩石可切割性标准的制定

• 批准号: 9612035
• 负责人: Emmanuel Detournay
• 金额: $ 18.43万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-01 至 2000-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9612035&HistoricalAwards=false
• 关键词: Development; Cuttability; Criteria; Rocks

9612035 Fragmentation of rock is important for many applications in rock engineering. The excavation of underground facilities is increasingly sought to accommodate the complex demands of today's society, and it is important to develop new ways to safely and cost-effectively remove rock, particularly hard rock. Very few mechanical excavators have been designed to operate in hard rock, basically because of a lack of knowledge of the cutting process. This research will lead to an improved understanding of the basic mechanisms involved in mechanical breakage of rock, and will thus ultimately contribute to improvements in the design and/or mode of operation of rock excavation machines. The main objectives of the proposed research are to develop (1) cuttability criteria and (2) and index test to evaluate the ability to cut rocks using mechanical indentor-type tools (such as disk cutters used on tunnel boring machines, TBMs). The essential mechanism involved in the mechanical breakage of rocks by indentation is the development of a crushed zone as a prelude to the formation of tensile cracks, which eventually cause chipping of the rock. The existence of this crushed zone imposes constraints on the efficiency or even the ability to cut rocks by mechanical means. Indeed, compressive damage of the rock beneath the indentor limits the magnitude of the compressive stress required to initiate and propagate tensile cracks. ***

9612035 岩石破碎在岩石工程中的许多应用中是重要的。 地下设施的挖掘越来越多地被寻求以适应当今社会的复杂需求，并且重要的是开发新的方法来安全且经济地移除岩石，特别是硬岩石。 很少有机械挖掘机被设计成在坚硬的岩石中工作，主要是因为缺乏对切割过程的了解。 这项研究将导致一个更好的理解的基本机制，涉及机械破碎的岩石，因此，最终将有助于改进的设计和/或操作模式的岩石挖掘机。 拟议研究的主要目标是开发（1）可切削性标准和（2）指数测试，以评估使用机械压头型工具（如隧道掘进机上使用的圆盘刀具，TBM）切割岩石的能力。 在岩石的机械破碎压痕的基本机制是一个破碎区的发展，作为一个前奏形成的拉伸裂纹，最终导致碎裂的岩石。 这种破碎区的存在对机械方式切割岩石的效率甚至能力施加了限制。 实际上，压头下方的岩石的压缩损伤限制了引发和扩展拉伸裂纹所需的压缩应力的大小。 ***