Feasibility Research on a Novel Rock Drill Concept

在硬岩中钻孔进行开挖和采矿施工，一般采用旋转冲击钻机。虽然在过去的二十年里，冲击钻井技术取得了进步，包括碳化钨钻头，但液压驱动和水射流工艺仍然被认为是缓慢和昂贵的。含有磨料的高压水射流钻井的新概念已经显示出相当大的前景，可以显著提高岩石钻井的生产率。该研究项目将包括设计、制造和测试一种新型磨料/水射流钻机，该钻机能够在不移动机械部件的情况下高速钻穿坚硬岩石。该设计包括一个带有高压喷嘴的钻头，以形成水射流。在高速射流形成后，磨料被送入散布器段的射流中。将对钻头的设计和制造进行评估，以确定不同钻速下的钻井参数，包括水压、水流、磨料类型、磨料流量、磨料尺寸和隔离距离。Flow Industries在开发磨料水射流切割系统方面拥有丰富的经验，可用于各种工业应用，包括车削，铣削，切割和表面精加工。首席研究员在水射流方面有超过15年的经验，是该领域的权威人士。我们预计这一成功的开发将在国际范围内大幅降低硬岩钻井作业的成本。建议颁发奖项。RUDNICKI这是与能源部（DOE）的一项合作研究。美国能源部为土工材料的剪切局部化分析提供设备和技术人员进行实验验证。该研究应用了最近的固体力学进展来理解剪切局部化行为，并开发了一种经过验证的方法来预测岩石和混凝土结构等岩土材料的稳定性。本工作的主要目标是了解土工材料中应变局部化的物理过程，并为将实验室观察结果外推到应用中提供理论框架。该研究对岩石和其他具有非弹性变形和非弹性体积变化敏感性的地质材料的剪切局部化进行了全面的研究。该研究将理论分析与计算和实验工作相结合。改进的多轴和非弹性变形的本构关系将被制定，一个框架将被开发用于本构模型在数值代码。具体来说，压力敏感和非弹性可压缩固体的剪切破裂将基于涉及均匀变形分叉的模型进行研究。局部化的研究将与实验观察和数值计算相结合，研究土工结构多轴变形的非弹性本构关系的性能。首席研究员是该领域应用于应变局部化的力学研究的领导者。这种合作研究具有成本效益，解决了固体和地质力学研究中的一个关键问题。

Drilling holes in hard rock for excavation and mining construction is generally carried out with rotary percussion drills. While advances have been made in percussion drilling in the past twenty years including tungsten carbide inserts, hydraulic actuation and water jet process is till classified as slow and expensive. New concepts of drilling with high pressure water jets containing abrasives have shown considerable promise and could significantly improve productivity in rock drilling. The research program will involve the design, fabrication and testing of a novel abrasive/water jet drill capable of drilling in hard rock at high speed with no moving mechanical components. The design incorporates a drill head with a high pressure nozzle to form a water jet. Abrasives are fed into the jet in the spreader section after the high velocity jet has been formed. The design and fabricaiton of the drillhead will be evaluated to determine the drilling parameters including water pressure, water flow rate, abrasive type, abrasive flow rate, abrasive size and stand-off distance for different penetration rates. Flow Industries have extensive experience in developing abrasive water jet cutting systems for a variety of industrial applications including turning, milling, cutting and surface finishing. The principal investigator has over 15 years experience with water jets and is a leading authority in the field. We anticipate a successful development which could lead to major cost reduction in hard rock drilling operation on an international scale. An award is recommended. 8612876 RUDNICKI This is a cooperative research with the Department of Energy (DOE). DOE provides the facility and technical personnel to perform experimental verfication for the analysis on shear localization of geo-materials. The research applies recent solid mechanics advances to understand shear localization behavior and develope a verified approach to predict the stability of geo-materials such as rock and concrete structures. The main goal of this work is to understand the physical process of strain localization in geo-materials and provide a theoretical framework for the extrapolation of laboratory observations to applications. The research performs comprehensive studies on shear localization in rocks and other geo-materials that exhibit sensitivity of inelastic deformation and inelastic volume change. The studies combine theoretical analyses with computational and experimental work. Improved constitutive relations for multiaxial and inelastic deformation will be formulated and a framework will be developed for the use of constitutive models in numerical codes. Specifically, shear rupture in pressure-sensitive and inelastically compressible solids will be investigated based on models involving bifurcation from homogeneous deformation. The investigations of localization will then be use with experimental observations and numerical calculations to study the performance of inelastic constitutive relations for multiaxial deformation of geo-structures. The Principal Investigator is a leader in this area of mechanics research applied to strain localization. This cooperative research is cost effective and addresses a critical problem in Solid and Geomechanics research.