基于板壳理论的充填开采覆岩导水断裂带发育规律

为分析充填开采时覆岩导水断裂带的发育规律,采用板壳理论分析了充填开采过程中关键层的破断力学过程,得到随着采厚的增加,导水断裂带是逐层向上发育,而不是随着采厚的增加渐进式发育;采用数值模拟的方法再现了采后不同充填高度时覆岩导水断裂带的发育规律,得出覆岩的"两带"发育随着等效采高的变化存在着临界效应,即充填体高度的量变,会引起覆岩变形破坏高度的质变。现场观测了充填工作面采后的覆岩导水断裂带发育情况,实测得到的结果与理论分析结果吻合,验证了上述理论分析和数值模拟得到的结论。

Development law of fractured zone of overburden strata in backfill mining based on plate and shell theory

In order to analyze the development law of overlying strata fracture zone in filling mining, the fracture mechanics process of key strata in filling mining was analyzed by using the theory of plate and shell. It is found that the water-conducting fault zone develops layer by layer with the increase of mining thickness, rather than progressive development with the increase of mining thickness. The numerical simulation method is used to reproduce the development law of overlying rock fracture zone at different filling heights after mining. It is concluded that the development of overlying rock "two zones"has a critical effect with the change of equivalent mining height, that is, the quantitative change of filling height will cause the qualitative change of the deformation and failure height of overlying rock. The development of overlying strata fracture zone after mining in filling working face is observed. The measured results are in agreement with the theoretical analysis results. The measured results verify the conclusions of the theoretical analysis and numerical simulation.