Behaviour and support of highly stressed pillars in deep mines and caving operations

深部矿山和崩落作业中高应力支柱的行为和支撑

• 批准号: 485174-2015
• 负责人: Cai, Ming
• 金额: $ 8.37万
• 依托单位: Laurentian University of Sudbury
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 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=618157
• 关键词: Behaviour; support; highly; stressed; pillars

This project aims at assisting mines at great depth (>2km) and mines extracting lower grade ore bodies by caving operations. Caving allows bulk mining of marginal and large ore bodies and is increasingly practiced by mining companies in Canada (e.g., Afton and possibly Diavik mines) and around the world. The proposed research will focus on pillar design with effective, deformable ground support. Experience shows that support installed in hard rock pillars is often ineffective because the support system cannot manage large deformations imposed by the bulking, fractured rock. The researchers will develop, in collaboration with the supporting sponsors, effective tools and techniques to improve pillar design and performance through effective support. It is proposed to focus on three pressing tasks: (1) Deformation-based support selection: matching deformation demand with the support's yield capacity; (2) Development of deformation resistant support components: including assessment of hybrid bolts as potentially the most effective bolts for deformable support systems; and (3) Time-dependent pillar loading: investigating processes resulting from compaction of fragmented rock in and above drawpoints. Effective and efficient support for mining sequences and draw strategies can only be achieved with better understanding of time-dependent load demand, rock deformation behaviour, and capacity of deformation-resistant support. Research approach includes back-analysis of results from physical model tests; in-situ monitoring of extraction level pillars; and in-situ testing of hybrid rock bolts supported by analytical and numerical model developments for reinforced, stress-fractured ground. Findings will assist in arriving at safe and more economic pillar dimensions with cost-effective support. Research will benefit financial and safety performances of Canadian mines, improve understanding of geo-engineering principles for design in stressed ground, and provide valuable opportunities for HQP training at Laurentian University.

本项目旨在协助大深度（20 ~ 2km）矿山和采用崩落法开采低品位矿体的矿山。崩落法允许大量开采边缘和大型矿体，加拿大（如阿夫顿矿和可能的迪亚维克矿）和世界各地的矿业公司越来越多地采用崩落法。拟议的研究将侧重于具有有效、可变形地面支撑的支柱设计。经验表明，安装在硬岩柱上的支护往往是无效的，因为支护系统无法控制岩石膨胀、破裂所造成的大变形。研究人员将与资助单位合作，开发有效的工具和技术，通过有效的支持来改善支柱的设计和性能。重点解决三个紧迫问题：(1)基于变形的支架选择：将变形需求与支架的屈服能力相匹配；(2)抗变形支撑部件的开发：包括混合螺栓作为潜在的最有效的可变形支撑系统螺栓的评估；(3)随时间变化的矿柱加载：研究由拉拔点及其上方的破碎岩石压实引起的过程。只有更好地了解随时间变化的载荷需求、岩石变形行为和抗变形支护能力，才能实现对采矿顺序和开采策略的有效和高效支持。研究方法包括对物理模型试验结果进行反分析；抽采水平柱的现场监测；并通过分析和数值模型的开发，对加固应力破碎地基进行了混合锚杆的现场试验。调查结果将有助于在具有成本效益的支持下达成安全和更经济的支柱层面。研究将有利于加拿大矿山的财务和安全性能，提高对应力地设计的地球工程原理的理解，并为劳伦森大学的HQP培训提供宝贵的机会。