煤柱影响下被保护层开采应力演化特征数值模拟研究  

Numerical simulation study on the evolution characteristics of mining stress for protected layer under the influence of coal pillar

作　　者：刘宜平[1] 朱恒忠 殷帅峰[3] LIU Yi-ping;ZHU Heng-zhong;YIN Shuai-feng(Anhui Wanbei Coal-electricity Group Co.LTD,Suzhou 234000,China;State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao 266590,China;Faculty of Safety Engineering,North China Institute of Science and Technology,Sanhe 065201,China)

机构地区：[1]安徽省皖北煤电集团有限责任公司,安徽宿州234000 [2]山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地,山东青岛266590 [3]华北科技学院安全工程学院,河北三河065201

出　　处：《煤炭工程》2020年第9期99-105,共7页Coal Engineering

基　　金：国家自然科学基金资助项目(51604114);“十三五”国家科技重大专项(2016ZX05067005-001);中央高校基本科研业务费项目(3142018035)。

摘　　要：为探究煤层群开采过程中,煤柱对被保护层开采应力演化特征的影响规律,以良村煤矿1801工作面为工程实际,应用FLAC3D应变-软化模型对煤柱影响下被保护层工作面开采时支承压力和三维应力的演化规律进行了数值模拟。研究结果表明:被保护层工作面除煤柱影响区之外整体处于卸压状态。支承压力演化规律与被保护层工作面开采进度紧密相关。当工作面推进位置处于煤柱影响区时,支承压力值突增至原岩应力的1.25倍,曲线呈快速上升态势。距离保护层的层位越高,垂直应力值越小,当层位距大于26m时,三维应力分布基本不再受煤柱的影响。煤柱影响下被保护层工作面范围可分为煤柱影响区、煤柱影响扩界区和卸压区,以此提出了瓦斯突出分区防治策略,在该工作面实施了高位穿层钻孔、采空区埋管瓦斯抽放、网状穿层钻孔和大直径卸压钻孔的综合措施,累计抽放瓦斯90余天,抽放瓦斯64805m3,效果检验指标均不超限,实现了安全回采。In order to explore the influence law of coal pillar on the evolution characteristics of mining stress for the protected seam in coal seam group mining,FLAC3D strain softening model is used to simulate the evolution law of support pressure and three-dimensional stress in the protected layer mining under the influence of coal pillar.The results show that the protected seam working face is in the pressure relief state except for the coal pillar influence area.The evolution law of abutment pressure is closely related to the mining progress of the protected seam.When the working face advances in the coal pillar influence area,the abutment pressure suddenly increases to 1.25 times of the original rock stress,and the curve shows a rapid rising trend.The higher the horizon is from the protective seam,the smaller the vertical stress value is.When the horizon distance is greater than 26m,the three-dimensional stress distribution is basically no longer affected by the coal pillar.Under the influence of coal pillar,the working face of the protected seam can be divided into three parts:coal pillar influence area,coal pillar influence expanding area and pressure relief area.At the same time,the comprehensive measures of high-level crossseam drilling,gas drainage by buried pipe in goaf,mesh cross-seam drilling and large-diameter pressure relief drilling are implemented in the working face.The total gas drainage was more than 90days,and 64805m3 gas was drained.The effect inspection indexes are not over limit,and the safe mining is realized.

关 键 词：被保护层开采 煤柱留设 支承压力 应力分布 瓦斯突出分区防治 

分 类 号：TD713[矿业工程—矿井通风与安全]