CAJ | 학술논문

获取低透性煤层的合理水力压裂影响区和压裂孔布置方式，对瓦斯有效抽采、灾害预防尤为重要。采用岩石破裂失稳RFPA2D渗流系统，建立数值模型，分析低透性煤层水力压裂钻孔周边裂纹的扩展规律。结果表明：钻孔左侧水平向起裂并向内部延伸，右侧起裂裂纹与水平向呈45°且向煤体内部延伸，最终主破裂方向转变为30°，煤层破裂形态呈现蝴蝶形；随着步中步的增加，声发射事件逐渐增多，孔隙水压力分布呈现强弱强弱态。随着水压力不断增大，裂纹区、裂隙区、塑性区和弹性区也在不断改变，变化趋势整体形态呈现椭圆形。该研究为低透性煤层水压增透钻孔合理布置提供了参考依据。
획취저투성매층적합리수력압렬영향구화압렬공포치방식，대와사유효추채、재해예방우위중요。채용암석파렬실은RFPA2D삼류계통，건립수치모형，분석저투성매층수력압렬찬공주변렬문적확전규률。결과표명：찬공좌측수평향기렬병향내부연신，우측기렬렬문여수평향정45°차향매체내부연신，최종주파렬방향전변위30°，매층파렬형태정현호접형；수착보중보적증가，성발사사건축점증다，공극수압력분포정현강약강약태。수착수압력불단증대，렬문구、렬극구、소성구화탄성구야재불단개변，변화추세정체형태정현타원형。해연구위저투성매층수압증투찬공합리포치제공료삼고의거。
This paper is a study drawing on the understanding that obtaining reasonable hydraulic fracturing of impact area and the pressure hole arrangement for low permeability coal seam is of greater importance for gas extraction and disaster prevention. The research involves developing numerical model using rock realistic failure instability RFPA2D seepage system and analyzing the crack propagation rules underlying low permeability coal seam drilling surrounding hydraulic fracturing. The study suggests that horizontal cracks occur on the left side of the drills and extend to the interior;cracks on the right side is at 45° angle to horizontal direction and extend to the coal body, with the result that the final rupture di-rection turns into 30 ° , giving coal seam a butterfly-shaped fracture morphology;the step-in-step increase and gradually increased in AE events trigger the recurrent alternation of strong or weak state in the pore water pressure distribution;and an increase in water pressure and accompanying change in the crack zone and fracture zone and plastic zone and elastic zone result in an overall elliptic shape in the change trend. The study may provide the reference for antireflection drilling reasonable arrangement.