基于“整条测线”应力变化确定超前支护距离的研究

Determination of Advance Support Distance Based on Stress Variation of Measuring Point Line

基于大量的钻孔应力数据,摒弃“分析单测点应力确定超前支护距离”的思维模式,以整条测线应力监测为研究对象,分析其随推采进度的变化特征,得到了超前支承压力变化规律,确定了准确的超前支护距离,结果表明:随工作面推进,测点位置不同,上覆岩层的破断高度不同,应力变化特征也不同,则确定的超前支护距离存在差异;与分析单测点应力变化相比,分析整条测线的应力变化特征得到的超前支护距离更准确;工作面未推采测线时,其应力曲线呈“近高远低”形态,工作面推采时,其应力曲线呈“近乎水平”形态,近水平跨距为90m。

Based on a large number of borehole stress data,the author adopts a new thinking mode to study the distribution law of the advance support pressure by analyzing the stress of the measuring point line instead of single measuring point,and finally determines the accurate advance support distance.The following conclusions are drawn:with the advance of coal mining face,when the location of the measuring point changes,the breaking height of the strata above the measuring point varies,as well as the stress change of the measuring point,so the final determined advance support distance is different compared with the analysis of the stress change of single measuring point,and the advance support distance obtained by analyzing the stress change characteristics of the measuring line is more accurate.When the mining face does not push the measuring point line,the stress curve presents the shape of“near-high,far-low”.When the mining face pushes the measuring point line,the stress curve presents the shape of“near-horizontal”,and the horizontal span is 90m.