地下采动山体变形活动的模型实验

A MODELLING RESEARCH INTO SLOPE DEFORMATION ACTIVITIES ASSOCIATED WITH UNDERGROUND MINING

本文在分析横山山体地质条件及因地下采空而诱发出的山体变形破坏特征的基础上,对采空区地表山体的变形破坏进行了工程地质力学模拟研究。结果表明,横山山体之下3号煤层的采动坍陷是引起山体变形破坏的直接原因;毗邻山体的电厂区地表隆起变形破坏,是因采空区上覆岩层在坍陷时所产生的向电厂方向的蠕动,致使厂区地基土遭受挤压和变形的结果;随着3号煤层采动的结束及其上覆岩层坍陷过程的完成,电厂区将会恢复到稳定状态。 通过分析,山体岩层倾角增大时有无地下采空影响的山体变形破坏的不同特征,得出了同时具有地表侵蚀临空面和地下采空临空面的山体与仅有地表侵蚀临空面之斜玻的山体变形破坏是不同的。从不同模型材料所得实验结果的一致性,验证了此模拟实验在理论上和实际中都有很好的相似性。

The geomechanical modelling research into the deformation failure induced by the underground mining is made in this paper, based on the analysis of the geological conditions of the Hengshan slope and the characteristics of the slope deformation.The result of the research shows that the mining and the collapsing of the coal seam No.3 under the Hengshan slope are the direct factors causing the slope deformation and failure.It also shows that the surface upwarding and the deformation damages of the area of the power plant next to the slope have been the results of the creep toward the plant which was produced during the collapsing of the overlying rock in the mining area, thus causing the plant's foundation soil to be squeezed, expressed and deformed.The power plant region will return to the stable state again as the mining of the coal seam No.3 ends and the collapsing of the strata overlying rock are finished.The paper brought to light the active mechanism of the surface slope above the mined-out area formed out of the low angle tilt rock layers.The stability trend of the Hengshan slope and the power plant area next to it was predicted according to the experiments results of the mined-out multiple coal seams under the ground. By means of the detail analysis of the slope deformation for the influence of the underground coal mining on the failure characteristics has been resoned in this paper as the angle of the slope strata increased.Thus the law that the activities of the slope which has a ground-face and the underground mining room are different from the one which has only the ground face has been known. The former has a typical geomechanic model of the squeezing and pressing-deep creeping-slope foot creeping and the later has a model of the slope foot tension-sliding-deep creeping-the back pulling apart. In addition, the concordance of the results obtained with different experimental materials proved the similarrity of the model experiments theoretically and practically.