【作者】 任高峰；

【导师】 张世雄；

【作者基本信息】 武汉理工大学 ， 采矿工程， 2010， 博士

【摘要】 露井联合开采时,采动效应会叠加,露天边坡会受到数个应力场作用,在复合采动影响下的边坡岩体的滑移机制与变形规律更加复杂。井工开采引起的露天边坡滑塌、地表塌陷、排土场滑坡等灾害事故频繁发生,增加了露天边坡及排土场的维护费用,带来巨大经济损失并影响矿山的生产安全。因此,必须研究露井联合开采作用边坡损害机理及其稳定性控制技术。本文以平朔煤炭工业公司安太堡矿不采区露井联合开采为工程背景,综合采用理论分析、现场地质调查与试验、岩层变形监测、室内数值计算等方法与手段,探讨露井联合开采作用下的边坡损害机理及其稳定性控制技术。论文的主要研究成果有：(1)观察到露井联合开采作用边坡的损害具有时空效应。在两种采动效应的联合作用下,边坡岩体出现两种典型的滑动现象,一为岩体沿坡面下滑,二为岩体向深部采空区移动。在井工开采初期,边坡岩体发生向边坡倾向方向的位移,位移速率较大；随着采空区覆岩垮落并充填采空区,边坡岩体位移以向采空区方向变形为主,且随着井工开采工作面的远离而逐步停止。(2)露井联合开采条件下采动边坡的位移量及位移速率明显增大,边坡岩体变形特征主要表现出地下采动变形的特点。(3)随着露天边坡和井工采空区空间位置关系的不同,以及边坡倾向与井工矿开采方向的变化,边坡位移范围及大小表现出较大差异。当井下采取“逆坡开采”时,边坡前期表现为向边坡临空面侧的“倾倒”变形,后期逐渐转为向坡体内的井下采空区的沉陷位移；当井下采取“顺坡开采”时,边坡上部岩体以采空沉陷位移为主,坡脚的保安矿柱整体向抗力较小的临空面移动；当井下采取“侧向切坡开采”时,边坡整体向临空面侧位移,地表移动盆地呈非对称分布,边坡坡脚表现出鼓胀变形特征。(4)露天边坡下井工矿存在复合采动时,浅部矿体开采所形成的冒落带、断裂带、弯曲带首先发展至露天边坡；而深部矿体开采所形成的“三带”又会对该区域重新扰动。对于浅部矿体开采所形成的采空区必须及时处理,防止二次扰动时出现复合采动覆岩的瞬间垮塌而形成较大冲击矿压灾害影响露天边坡稳定。(5)露井联合开采作用边坡,可从多方面考虑提高其稳定性,如留设足够宽度的保安矿柱以承受井采过程中所形成的偏压；二是进行边坡上部的削坡减载以减小偏压,减缓坡脚保安矿柱中的应力集中；三是坡脚的压脚回填,有利于增加边坡抗滑力；四是对于边坡表层出现的采动裂隙,及时填平压实,避免雨水下渗,影响边坡稳定。(6)在了解露井联合开采作用边坡损害机理的基础上,综合考虑矿山开采废石运输功最小化、矿山开采环境影响最小化,提出了露井联合开采作用边坡稳定性控制快速护坡与生态恢复新技术。更多还原

【Abstract】 In the condition of underground mining combined with open-pit mining, mining effect will be superposed. Mining slope will receive several induced stress fields and the sliding mechanism and deformation law of slope rock mass will be more complicated. Frequent occurrence of accidents of open pit slope collapse and surface subsidence, landslides and other disasters dump caused by underground mining leading to an increase of the open slope and dump maintenance costs, brought about huge economic losses, what’s more, the direct impact on mine safety production. Therefore, the research on Slope Damage Mechanism and control technology under the combinational action of two mining approaches is necessary. This paper, taking Pingshuo Coal Industry Corporation Antaibao not mining district of combined mining as engineering background, adopts methods and means of theoretical analysis, field geological survey and test pit and underground mining effect of slope and rock mining damage related to deformation monitoring, indoor numerical calculation to explore the role of open pit and underground mining slope damage mechanism and the technology of Slope Stability Control. The main research results are:(1) The damage mechanism of slope shows time-and-space effects under circumstances in which both underground mining and open-pit mining are employed, and slope mass will emerge two typical sliding phenomenon with joint effects:the one is rock mass sliding along the slope, and the other droping to the deep mining gob. Rock mass will produce the overall displacement along slope inclination with a relative high rate in the early period of underground mining. However, the movement will gradually tend to be stable with overburden rock caving and filling into mining gob.(2) Displacement and movement rate of slope mass increases obviously in the situation of joint effect than that single open-pit mining, and slope movement in combinational mining mainly exhibits as the deformation caused by underground mining.(3) Slope displacement range and size shows quite difference associated with different spatial relations between open pit slope and mining gob and direction of slope inclination and mining exploitation. In the condition of reverse slope mining, slope mass dumps to free face in early-stage and then gradually turn to subsidence movement inside slope. While down-slope mining, rock mass at the top of slope mainly conducts subsidence displacement to gob, and security mining pillars at the foot move to less resistance free-surface. And in the situation of lateral cut slope mining, slope makes the whole movement to its free-face. Surface movement basin appears non-symmetrical distribution and slope foot presents bulging deformation.(4) Under the complex mining condition, caving zone, fault zone and bending zone caused by shallow ore body mining develop to pit slope firstly, and then the "three zones" in deep ore mining will effect on the area. Therefore measures and solutions should be done in time to deal with the shallow mining gob to prevent large rock-burst disaster caused by sudden collapse of overlying strata due to second disturbance.(5) There are many different perspectives to improve slope stability in the condition of combinational mining. Firstly, adequate width security pillar should be provided in advance to withstand bias formed during underground mining; the second is to cut some top of slope to reduce the bias load shedding to mitigate stress concentration of the security pillars at the foot; thirdly, filling back of foot slope can help to increase skid-resistance; fourth, surface cracks appearing on slope should be filled compaction to avoid rainwater seeping down and the influence to slope.(6) Slope stability control and slope maintaining quickly and ecological restoration technology are proposed under condition of open-pit mining combined with underground mining based on understanding slope damage mechanism, considering minimize transport work of goaf and minimize environmental impacts of mining.更多还原