厚松散层覆岩移动机理及“类双曲线”模型  

Movement mechanism and analogous hyperbola model of overlying strata with thick alluvium

作　　者：左建平[1,2] 孙运江[2] 钱鸣高[1,3] 

机构地区：[1]中国矿业大学(北京)煤炭资源与安全开采国家重点实验室,北京100083 [2]中国矿业大学(北京)力学与建筑工程学院,北京100083 [3]中国矿业大学(北京)资源与安全工程学院,北京100083

出　　处：《煤炭学报》2017年第6期1372-1379,共8页Journal of China Coal Society

基　　金：国家自然科学基金优秀青年基金资助项目(51622404);国家自然科学基金资助项目(51374215);"十三五"国家重点研发计划联合资助项目(2016YFC0801404)

摘　　要：现场大量工程实践表明厚松散层移动与常规基岩移动有所差异。目前岩层移动规律的研究主要侧重在两方面:一方面是采场岩层控制主要研究煤层附近顶板基岩的破断和移动规律,另一方面是地测工程主要研究地表松散层的沉降规律。将这两者有机相联,希望能更精准反映基岩和松散层的整体变形及移动规律。基于基岩初次断裂和周期断裂力学模型,获得了主拉应力的分布规律和破断迹线,揭示了基岩的倒漏斗型破断机理;结合概率积分法和剪切滑移理论分析了厚松散层的漏斗型移动机理。由此认为厚松散层覆岩的整体移动呈现"类双曲线"特征,并建立了岩层整体移动的"类双曲线"模型,可更好的预测地表沉陷范围。运用改进的采矿不连续变形分析程序MDDA模拟获得了厚松散层覆岩"类双曲线"型破断运移规律,一定程度上验证了理论模型的合理性。A large number of field engineering practice indicate that the movement of thick alluvium rock strata has a large difference with that of bedrock. At present, the rock strata movement laws mainly focus on two aspects. Strata control above working face mainly researches on the fracture and movement laws of roof rocks with a certain height at one side. However, the geology and survey engineering mainly researches on the subsidence laws of surface thick allu- vium at another side. In this paper, the authors try to combine the two research areas and develop a new rock strata movement model, which can accurately reflect the true movement law of overlying strata. Based on the initial and peri- odic fracture mechanical models of bedrock, the distribution of principal stress and the fracture trace have been ob- tained. And the inverse funnel-shaped failure mechanism is the main failure mechanism of deep bedrock. The funnel- shaped movement mechanism of shallow thick alluvium has been discussed in detail based on probability integralmethod and shear-slip theory. Combined the two aspects of researches, the paper proposes that the movement of overly- ing strata with thick alluvium has the feature of analogous hyperbola. In addition, the analogous hyperbolic movement model is proposed to characterize the movement of overlying strata with thick alluvium. The new model can be used to predict overlying strata＇ s subsidence range. The Mining Discontinuous Deformation Analysis （MDDA） has been de- veloped and applied to simulate the movement of overlying strata with thick alluvium. Numerical results indicate that the analogous hyperbolic movement laws can also be founded, which is approximately consistent with the theoretical model.

关 键 词：厚松散层 关键层 覆岩破断与移动 类双曲线 MDDA 

分 类 号：TD325[矿业工程—矿井建设]