基于稳压区理论近距离上下煤层协同开采错距研究

Study on misspacing of close distance cooperative mining of upper and lower coal seams based on stable pressure zone theory

为研究近距离上下煤层协同开采工作面走向错距问题,以某煤矿12号、13上号煤层联合布置同采为工程背景,利用稳压区理论对上下煤层的工作面同时开采时覆岩运动规律进行研究,建立近距离煤层同采时的采场覆岩力学结构模型,对12号煤层和13上号煤层工作面同时回采的错距作出合理的选取,并进行现场实践验证。结果表明:12号煤层与13上号煤层的同采错距应控制在40~50 m范围内,此时两煤层采场的相互扰动影响最小。13上号工作面布置在12号煤采空区压实区域时,采空区上方覆岩逐渐稳定,12号煤开采对13上号煤工作面扰动影响程度小,矿山压力变化不明显。上下煤层协同开采时13上号煤层的工作面支护形式为大采高支架,综采采用一次采全高全部垮落法回采工艺。近距离煤层同采走向错距方案应用于现场实践,上下煤层工作面生产状况良好,表明了选取的安全错距能够满足安全生产。

In order to study the mismatch problem of the strike of the working face in the cooperative mining of the upper and lower coal seams,taking the joint arrangement of the No.12 and No.13 coal seams of a coal mine as the engineering background,the theory of stable pressure zone is used to study the movement law of the overburden when the working face of the upper and lower coal seams is mined simultaneously,and the mechanical structure model of the overburden of the stope when the close coal seams are mined simultaneously is established.the wrong distance of mining in No.12 coal seam and No.13 coal seam at the same time is chosen reasonably and verified by field practice.the results show that the co-mining misdistance of No.12 coal seam and No.13 coal seam should be controlled in the range of 40 m~50 m,at this time,the mutual disturbance influence of the two coal seams is minimal.when the No.13 working face is arranged in the No.12 mined-out area,the overlying rock above the mined-out area is gradually stable.the influence of No.12 coal mining on the No.13 coal working face disturbance is small,and the change of mine pressure is not obvious.when the upper and lower coal seams are cooperatively mined,the working face support form of no.13 coal seam is large mining height support,and the fully mechanized mining adopts the all-height and all-caving mining technology in one mining.the misspacing scheme in the same mining direction of close coal seam is applied to the field practice,and the production condition of the upper and lower coal seam working face is good,which indicates that the selected safe misspacing can meet the safety production.