断续节理岩体及岩质边坡破坏的细观机制

发布时间：2018-11-05 19:37

【摘要】：以赞比亚穆利亚希北露天铜矿边坡为工程背景,基于颗粒流理论及PFC2D程序,将岩块和节理分别用颗粒体模型与光滑节理模型表征,构建含2条断续节理岩体及顺层断续节理岩质边坡模型,从细观力学角度深入研究其破坏过程中的力学机制。断续节理岩体破坏研究表明:岩桥破坏模式可划分为模式I、模式II、模式III a和模式III b破坏4类,且各类模式本质上均是以矿物颗粒间黏结张拉破坏为主的微破裂引起。顺层断续节理岩质边坡破坏研究表明:滑坡产生的微破裂主要从坡底断续节理端部开始产生,逐渐向坡体上部发展;滑体底部形态较为平直,而后部形态较为曲折并呈台阶状破坏;滑坡产生的破碎颗粒体先在边坡面中、下部产生,其体积相对较小,随后在边坡上部产生,其体积相对较大;在滑坡过程中,节理端部岩桥连线方向上的颗粒接触力较大,产生的微震事件强度与次数的关系近似服从正态分布函数。
[Abstract]:Based on the theory of particle flow and PFC2D program, the rock masses and joints are represented by particle body model and smooth joint model, respectively, based on the engineering background of the slope of Muliach-Bei opencast copper mine in Zambia. The model of rock slope with two discontinuous joints and bedding jointed rock mass is constructed, and the mechanical mechanism in the process of failure is deeply studied from the viewpoint of meso-mechanics. The study on the failure of intermittent jointed rock mass shows that the failure mode of rock bridge can be divided into four types: mode I, mode II, mode III and mode III b failure, and all the models are essentially caused by the microfracture of mineral intergranular bond tensioning failure. The study on the failure of rock slope with interbedded intermittent joints shows that the microfracture of the slope begins from the end of the discontinuous joint at the bottom of the slope and gradually develops to the upper part of the slope body; The shape of the bottom of the sliding body is more straight, while the shape of the back part is more zigzag and destructed, and the broken particles produced by the landslide occur first in the slope surface, in the lower part, its volume is relatively small, and then in the upper part of the slope, its volume is relatively large. In the process of landslide, the contact force of particles in the connection direction of the rock bridge at the end of the joint is large, and the relationship between the intensity of the microseismic events and the number of times is approximately fitted to the normal distribution function.
【作者单位】：北京科技大学金属矿山高效开采与安全教育部重点实验室;中国有色矿业集团有限公司;
【基金】：国家青年科学基金资助项目(51504016) 科技北京百名领军人才培养工程(Z151100000315014) 中央高校基本科研业务费专项资金资助项目(FRF TP 15 036A2)~~
【分类号】：TD31;TD854.6

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