切顶卸压自成巷技术在浅埋中厚煤层开采中的应用

Application of gob-side entry retaining formed by roof cutting and pressure release in shallow-buried medium-thick seam mining

基于岩体碎胀特性是切顶卸压沿空留巷技术切顶参数计算和设计的关键,本文以哈拉沟煤矿12201工作面为工程背景,通过现场实测、理论分析等方法对采空区矸石碎胀特性及控制技术进行研究。现场实测表明:采空区顶板从垮落、压实到稳定,经历了三个过程,确定了每个过程的影响范围与时间效应,准确地测出采空区顶板稳定后的碎胀系数k为1.35~1.40,确定了切顶深度6m的合理性。通过建立冒落矸石稳定后力学模型,揭示了冒落矸石与留巷巷内支护的协同作用原理,提出了在工作面支架后挡矸装置采用由11#工字钢、金属网以及单体液压支柱联合而成体系进行支护,最后取得了良好的成巷效果。

The broken expand characteristics based on the rock mass,are the key to the calculation and design of the roof cut parameters of gob-side entry retaining technology.Taking the 12201 working face of Halagou coal mine as the engineering background,it was deduced by field measurement and theoretical analysis to study the broken expand characteristics and the control technology of gangue in the goaf.The on-site measurement results show that the roof of the goaf has undergone three processes from fall,compaction and stabilization,and the impact scope and time effect of each process could been determined;the broken expansion coefficient k after the stability of the roof in the goaf area has been accurately measured from 1.35 to 1.40,and the rationality of the 6 m cut depth was determined.Through the establishment of the mechanical model after the stability of the caving gangue,the principle of synergistic action between falling gangue and roadway support in gob-side entry retaining is revealed,and the supporting system of the single hydraulic prop,11 #I-steel and the reinforcing steel net is put forward,and the good effect of the roadway is achieved.