基于应变软化模型的抽采钻孔封孔段稳定性研究  

Stability Analysis of Sealing Section in Gas Extraction Hole Based on Strain Softening Model

作　　者：王志明[1] 王永龙[1] 刘春[2] 夏同强[3] 

机构地区：[1]河南理工大学能源科学与工程学院,河南焦作454000 [2]中国矿业大学物联网(感知矿山)研究中心,江苏徐州221008 [3]中国矿业大学电力工程学院,江苏徐州221008

出　　处：《煤矿安全》2016年第4期6-10,共5页Safety in Coal Mines

基　　金："十二五"国家科技支撑计划资助项目(2013BAA03B02);河南省高校基本科研业务费专项资金资助项目(NSFRF140135)

摘　　要：为了解决软弱煤层中瓦斯抽采钻孔漏气严重的问题,基于煤岩体黏聚力沿塑性区线性弱化的应变软化模型,采用理论推导的方法得出了应变软化效应下抽采钻孔封孔段围岩的应力、位移及塑性范围的求解公式,利用数值模拟的方法对抽采钻孔封孔段围岩稳定性进行了数值模拟研究。研究表明:基于煤岩体应变软化模型钻孔围岩的塑性区范围及孔壁位移显著大于未考虑煤岩体应变软化效应的结果;随着孔内压力的增大,钻孔塑性区缩小,孔壁位移降低,钻孔的变形破坏受到抑制,且服从应变软化模型的围岩变形更易受到孔内压力的抑制。研究成果应用于河南某煤矿软弱煤层的瓦斯抽采封孔实践,表明在该矿软弱煤层瓦斯抽采中采用具有主动支护作用的囊袋式封孔法较聚氨酯封孔法瓦斯抽采浓度提高约18.1%,取得了良好的抽采效果。For solving the problem that serious gas leakage from the drainage hole,based on the strain- softening model whose cohesion reduces along the plastic area,the stability of the rock around the sealing section was researched. The methods of theoretical deduction and numerical simulation were adopted for the research. Research shows that the plastic area and displacement gets a significant increase in the rock around the hole. With the raise of the pressure in the hole,the plastic area of the wall rock and the displacement of the hole wall are reduced; the borehole tends to be more steady. Research findings were applied to sealing practices of gas extraction in a coal mine in Henan province; it shows that in the soft coal seam,the gas concentrate can improve more than 18. 1% with pocket assay grouting sealing method rather than polyurethane sealing method.

关 键 词：应变软化模型 钻孔稳定性 囊袋式封孔法 封孔段 瓦斯抽采钻孔 

分 类 号：TD713[矿业工程—矿井通风与安全]