Geomechanical design of cemented paste backfill systems (phase III)

胶结膏回填系统地质力学设计（第三期）

• 批准号: 514220-2017
• 负责人: Grabinsky, Murray
• 金额: $ 7.82万
• 依托单位: University of Toronto
• 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=618140
• 关键词: Geomechanical; design; cemented; paste; backfill

Underground mining creates large voids which must be backfilled to support the surrounding rockmass and limit the potential for violent rockbursts and large ground movements. An increasingly popular form of backfilling is Cemented Paste Backfill (CPB), which can be delivered relatively quickly and so accelerates the rate of mining, thereby enhancing the Net Present Value of the mineral reserve. It also re-uses tailings which would otherwise typically be pumped to a surface tailings pond, and so has positive environmental impacts. Much has been done in the last two decades to increase the effectiveness and efficiency of CPB systems. There are however a few design challenges left that, if addressed, can dramatically improve CPB's impact on mining operations. Improved structural analyses are required to safely design and construct the barricades that hold back CPB from the rest of the mine workings. Better predictions of how fast the CPB transitions from "slurry" to "solid" are needed so that the mine can resume production blasting near the backfill as quickly as possible. And an improved understanding of how CPB can be self-supporting when undermined is needed so that more effective mine planning strategies can be adopted.The proposed work is a continuation of an ongoing multi-year, industry funded project. NSERC's involvement in the final stage of this work will facilitate an expanded scope of laboratory research, generating new test techniques to better predict the maximum pressures exerted on fill barricades, and new knowledge about CPB resistance to dynamic loads. These fundamental results will in turn aid in a better interpretation of prototype field trials, and lead to new design approaches for specifying backfill barricades and for mining under backfill.

地下采矿会产生巨大的空隙，必须回填以支撑周围的岩体，并限制发生剧烈岩爆和大规模地面移动的可能性。一种越来越受欢迎的充填形式是水泥膏体回填（CPB），它可以相对快速地交付，从而加快采矿速度，从而提高矿产储量的净现值。它还重新利用了尾矿，否则这些尾矿通常会被泵送到地表尾矿池，因此对环境产生了积极的影响。在过去的二十年里，已经做了很多工作来提高CPB系统的有效性和效率。然而，还有一些设计上的挑战，如果得到解决，可以大大提高CPB对采矿业务的影响。需要改进的结构分析，以安全地设计和建造路障，阻止CPB从其余的矿井工作。需要更好地预测CPB从“泥浆”到“固体”的转变速度，以便矿山能够尽快恢复回填附近的生产爆破。此外，还需要更好地了解CPB在受到破坏时如何自我支持，以便采取更有效的采矿规划战略。拟议的工作是一个正在进行的多年期行业资助项目的延续。NSERC参与这项工作的最后阶段将有助于扩大实验室研究的范围，产生新的测试技术，以更好地预测施加在填充路障上的最大压力，以及有关CPB抵抗动态载荷的新知识。这些基本的结果将反过来有助于更好地解释原型现场试验，并导致新的设计方法，指定回填路障和回填下开采。