岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2015年
2期
444-450
,共7页
程亮%卢义玉%葛兆龙%丁红%钟定云
程亮%盧義玉%葛兆龍%丁紅%鐘定雲
정량%로의옥%갈조룡%정홍%종정운
水力压裂%倾斜煤层%地应力%坐标转换%起裂压力
水力壓裂%傾斜煤層%地應力%坐標轉換%起裂壓力
수력압렬%경사매층%지응력%좌표전환%기렬압력
hydraulic fracturing%inclined coal seam%in-situ stress%coordinate conversion%initiation pressure
针对目前倾斜煤层起裂机制不明确,导致水力压裂时盲目升高压力或增大注水量来增加煤层透气性的问题,根据最大拉应力理论,分析真实环境下倾斜煤层压裂钻孔周围应力状态,建立压裂钻孔周围煤岩体起裂压力计算模型及判断准则,并在重庆松藻煤电公司同华煤矿进行了验证,结果表明,根据实测压裂区域地应力状态,起裂压力随煤层倾角增大而增大,钻孔起裂位置随煤层倾角增大逐渐向走向方向偏转;现场试验起裂压力与理论计算相符,随煤层倾角增大而增大,从而验证了计算模型的正确性。
針對目前傾斜煤層起裂機製不明確,導緻水力壓裂時盲目升高壓力或增大註水量來增加煤層透氣性的問題,根據最大拉應力理論,分析真實環境下傾斜煤層壓裂鑽孔週圍應力狀態,建立壓裂鑽孔週圍煤巖體起裂壓力計算模型及判斷準則,併在重慶鬆藻煤電公司同華煤礦進行瞭驗證,結果錶明,根據實測壓裂區域地應力狀態,起裂壓力隨煤層傾角增大而增大,鑽孔起裂位置隨煤層傾角增大逐漸嚮走嚮方嚮偏轉;現場試驗起裂壓力與理論計算相符,隨煤層傾角增大而增大,從而驗證瞭計算模型的正確性。
침대목전경사매층기렬궤제불명학,도치수력압렬시맹목승고압력혹증대주수량래증가매층투기성적문제,근거최대랍응력이론,분석진실배경하경사매층압렬찬공주위응력상태,건립압렬찬공주위매암체기렬압력계산모형급판단준칙,병재중경송조매전공사동화매광진행료험증,결과표명,근거실측압렬구역지응력상태,기렬압력수매층경각증대이증대,찬공기렬위치수매층경각증대축점향주향방향편전;현장시험기렬압력여이론계산상부,수매층경각증대이증대,종이험증료계산모형적정학성。
As for the problem of ambiguous mechanism of crack initiation in inclined coal seam, it leads to a blind increase in water pressure or water injection rate to enhance the coal seam permeability during hydraulic fracturing in underground coal mines.In this paper, the stress state around the fracturing boreholes is analyzed using the in-situ stress coordinate conversion, then a model is established using the maximum tension stress (MTS) theory to calculate the initiation parameters of the borehole rocks. The influences of in-situ stress and coal seam inclination on the hydraulic fracturing initiation pressure and locations in underground coal mines are investigated using the model. The field test is conducted at Tonghua coal mine of Chongqing Songzao Coal and Electricity Co. Ltd. .The results show that: according to the stress state in fracturing area, the crack initiation pressure increases along with the increasing coal inclination. With the increase in the coal inclination, initiation location moves to the strike direction. The results in field test are consistent with the calculated result which is that initiation pressure increases along with increasing coal inclination. It verfies the feasibility of the calculation model.