煤矿开采地表沉陷盆地边界的再认识

Reconsideration of surface subsidence basin boundary induced by coal mining

为了研究厚松散层条件下煤矿开采沉陷盆地边界的界定及其影响因素,基于现场实测资料和误差传播定律,建立了厚含水松散层条件下地表沉陷监测点点位中误差函数模型;以辛置煤矿五采区为工程背景,采用UDEC离散元数值分析方法,揭示了采动程度与边界角之间的协同作用关系。研究结果表明:不同国家对沉陷盆地边界的界定并不统一,厚含水松散层条件下,沉陷盆地边缘15 mm的水平移动点可作为沉陷盆地的边界,对于特级保护对象,建议以2 mm下沉点作为沉陷盆地的边界。随着采动程度的增加,沉陷盆地上、下山边界角呈现先缓慢减小再逐渐增加的趋势,二者服从Lorentz函数模型,相关度分别为0. 88和0. 99,该函数模型能够表达研究区域采动程度与边界角之间的内在联系。

In order to study the definition and influence factors of subsidence basin boundary induced by coal mining under the condition of thick unconsolidated layers,a functional model of mean square error for the positions of surface subsidence monitoring points under the condition of thick water-bearing unconsolidated layers was established based on the in-situ measurement data and the error propagation law.Taking the 5 th mining section in Xinzhi coal mine as the engineering background,the synergistic interaction between the mining degree and the limit angle was revealed by using the UDEC discrete element numerical analysis method.The results showed that different countries had different definitions of subsidence basin boundary,and the horizontal movement points being 15 mm away from the edge of subsidence basin could be taken as the boundary of subsidence basin under the condition of thick water-bearing unconsolidated layers.For the specific protected object,it was recommended that the subsidence points of 2mm could be taken as the boundary of subsidence basin.With the increase of mining degree,the limit angles at the rise-side and dip-side of subsidence basin slowly decreased first and then increased gradually.Both of them followed the Lorentz functional model,and the correlation degree was 0.88 and 0.99 respectively.This functional model could express the interrelation between the mining degree and the limit angle in the studied area.