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 alluvium 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 periodic fracture mechanical models of bedrock,the distribution of principal stress and the fracture trace have been obtained.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 integral method and shear-slip theory.Combined the two aspects of researches,the paper proposes that the movement of overlying 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 developed 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.
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