A Discrete Fracture Network approach to rock mass characterization and assessment of rock fragmentation for cave mining.

用于岩体表征和洞穴采矿岩石破碎评估的离散裂缝网络方法。

• 批准号: 435667-2013
• 负责人: Elmo, Davide
• 金额: $ 1.75万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=636555
• 关键词: Discrete; Fracture; Network; approach; rock

Building on the increasing use of Discrete Fracture Networks (DFN) models in both mining and civil engineering applications, the proposed research has two major inter-related topics, which could be developed in parallel. The first topic includes studying the relationship between fracture length and volumetric fracture intensity in an attempt to quantitatively define the relationship between these parameters and the rock mass natural fragmentation. It is expected that this initial work will have a significant importance in helping defining the scale at which geomechanical synthetic rock mass models need to be simulated to fully capture the Representative Elementary Volume (REV) of a naturally fractured rock mass. The second topic involves focusing on pre caving assessment and in particular on rock mass fragmentation, since the impact of poor or unexpected fragmentation upon cave operations represents a significant engineering and economics factor. Research to date has certainly contributed to demonstrate that DFN tools can effectively assist in the fragmentation assessment, primarily through providing a better description of the natural fragmentation of the in-situ rock mass. However, the evaluation of primary and secondary fragmentation is still being carried out using alternative methods mostly based on practical experience, attempting to describe these processes using empirically derived rules rather than a direct solution of the processes and mechanisms involved. It is believed that synthetic testing of DFN based rock mass models, by means of hybrid Finite/Discrete Element simulation of rock breakage, can be effectively used to better capture fragmentation mechanisms and develop an alternative approach to aid fragmentation assessment in mining and civil applications. The proposed approach would rely not only on the ability to fully capture the broader heterogeneity of the rock mass, but more importantly on the ability of determining a critical fracture intensity value at which the transition from intact massive rock mass to kinematically mobile rock mass occurs.

拟议的研究以越来越多的使用在采矿和土木工程应用中使用离散裂缝网络（DFN）模型的基础上，有两个主要相关的主题，可以并行开发。第一个主题包括研究断裂长度与体积断裂强度之间的关系，以定量定义这些参数与岩体质量自然碎片之间的关系。可以预期，这项初始工作将在帮助定义需要模拟地质机械合成岩体模型的规模方面具有重要意义，以完全捕获自然断裂的岩体的代表性基本体积（REV）。第二个主题涉及专注于洞穴前的评估，尤其是岩石质量破碎化，因为贫困或意外碎片对洞穴操作的影响是一个重要的工程和经济因素。迄今为止的研究无疑有助于证明DFN工具可以有效地帮助进行分裂评估，这主要是通过更好地描述对原位岩石质量的自然碎片化的描述。但是，主要基于实际经验的替代方法，仍在使用替代方法进行评估，试图使用经验得出的规则来描述这些过程，而不是直接解决所涉及的过程和机制的直接解决方案。据认为，通过混合有限/离散元素模拟岩石破裂的综合测试可有效地用于更好地捕获碎裂机制，并开发出一种替代方法来帮助采矿和民用应用中的分裂评估。所提出的方法不仅依赖于完全捕获岩石质量更广泛的异质性的能力，而且更重要的是，确定从完整的巨大岩体质量到运动学上移动岩体的过渡的临界裂缝强度值的能力。