PRIMARY RESEARCH OF INFLUENCE OF UNSTEADY SEEPAGE PROCESSES ON HYDRAULIC FRACTURING IN ROCK MASS
WANG Yuan1，2，YAN Qingqing1，2
(1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering，Hohai University，Nanjing，
Jiangsu 210098，China；2. Institute of Tunnel and Metro Engineering，College of Civil and Transportation Engineering，
Hohai University，Nanjing，Jiangsu 210098，China)
Abstract：Hydraulic fracturing is a frequent problem in petroleum extraction，dam safety monitoring，in-situ geostress testing，tunnel-groundwater inrush prevention，etc. Firstly，a one-dimensional model considering unsteady seepage is established and its analytical solutions are derived. Comparing the calculated key factors (water pressure and hydraulic gradient) of hydraulic fracturing with the simulated result by finite element method，accuracy of these theoretical solutions is proved. Secondly，in terms of comparison with the result only considering steady status，it is presented that hydraulic gradient gets maximum as soon as water pressure increases in unsteady process. By contrast，hydraulic gradient gradually decreases and tends to be stable when reaching steady seepage status. Finally，the effect of rock permeability on hydraulic fracturing is also studied. The probability that hydraulic fracturing happens grows higher while the permeability is lower. In summary，it is essential to consider unsteady seepage status in mechanism study of hydraulic fracturing.
王 媛1，2，颜青青1，2. 岩体水力劈裂非稳定渗流影响机制初探[J]. 岩石力学与工程学报, 2012, 31(10): 2016-2021.
WANG Yuan1，2，YAN Qingqing1，2. PRIMARY RESEARCH OF INFLUENCE OF UNSTEADY SEEPAGE PROCESSES ON HYDRAULIC FRACTURING IN ROCK MASS. , 2012, 31(10): 2016-2021.
[1] 刘允芳，刘元坤. 水压致裂法三维地应力测量方法的研究[J]. 地壳变形与地震，1999，19(3)：64–71.(LIU Yunfang，LIU Yuankun. Study on 3D geostress determining method with hydrofracturing technique[J]. Crustal Deformation and Earthquake，1999，19(3)：64–71.(in Chinese))
[2] 葛洪魁，林英松，王顺昌. 水力压裂地应力测量有关技术问题的讨论[J]. 石油钻采工艺，1998，20(6)：53–62.(GE Hongkui，LIN Yingsong，WANG Shunchang. Discussion of technical problems on hydraulic fracturing geostress measurements[J]. Oil Drilling and Production Technology，1998，20(6)：53–62.(in Chinese))
[3] MORGENSTERN V，MORGENSTERN N R，VAUGHAN P R. Some observation on allowable grouting pressures[C]// Proceedings of Grouts and Drill Conference. London：Institute of Civil Engineering，1963：36–42.
[4] WONG H Y，FARMER I W. Hydro-fracture mechanisms in rock during pressure grouting[J]. Rock Mechanics and Rock Engineering，1973，5(1)：21–41.
[5] 陈愈炯. 土坝坝体的防渗灌浆[J]. 水利水电技术，1980，(2)：1–7. (CHEN Yujiong. Grouting seepage control of dam[J]. Water Resources and Hydropower Technologies，1980，(2)：1–7.(in Chinese))
[6] JULIAN B R，FOULGER G R，MONASTERO F C，et al. Imaging hydraulic fractures in a geothermal reservoir[J]. Geophysical Research Letters，2010，37(7)：1–5.
[7] HUBBERT M K，WILLIS D G. Mechanics of hydraulic fracturing[J]. Petroleum Transactions AIME，1957，210(1)：153–168.
[8] NOBARI E S，LEE K L，DUNCAN J M. Hydraulic fracturing in zoned earth and rockfill dams[R]. Berkley，California：University of California，1973.
[9] 丁金栗，孙亚平. 水力劈裂试验中击实土厚壁筒应力分析[J]. 水利学报，1987，(3)：16–22.(DING Jinli，SUN Yaping. Analysis of stress of thick wall cylinder of compacted soil in hydraulic fracturing experiment[J]. Journal of Hydraulic Engineering，1987，(3)：16–22. (in Chinese))
[10] 阳友奎，肖长富，吴 刚，等. 不同地应力状态下水力压裂的破裂模式[J]. 重庆大学学报：自然科学版，1993，16(3)：30–35.(YANG Youkui，XIAO Changfu，WU Gang，et al. Hydrofracturing breakdown modes under different in-situ stress states[J]. Journal of Chongqing University：Natural Science，1993，16(3)：30–35.(in Chinese))
[11] 詹美礼，岑 建. 岩体水力劈裂机制圆筒模型试验及解析理论研究[J]. 岩石力学与工程学报，2007，26(6)：1 173–1 181.(ZHAN Meili，CEN Jian. Experimental and analytical study of hydraulic fracturing of cylinder sample[J]. Chinese Journal of Rock Mechanics and Engineering，2007，26(6)：1 173–1 181.(in Chinese))
[12] 阳友奎，肖长富，邱贤德，等. 水力压裂裂缝形态与缝内压力分布[J]. 重庆大学学报：自然科学版，1995，19(3)：20–26.(YANG Youkui，XIAO Changfu，QIU Xiande，et al. Fracture geometry and pressure distribution in fracture for hydrofracturing[J]. Journal of Chongqing University：Natural Science，1995，19(3)：20–26.(in Chinese))
[13] 黄润秋，王贤能，陈龙生. 深埋隧道涌水过程的水力劈裂作用分析[J]. 岩石力学与工程学报，2000，19(5)：573–576.(HUANG Runqiu，WANG Xianneng，CHEN Longsheng. Study on the effect of hydraulic fracturing during water gushing in deep tunnel[J]. Chinese Journal of Rock Mechanics and Engineering，2000，19(5)：573–576.(in Chinese))
[14] 李宗利，任青文. 自然营造力作用下岩体混凝土水力劈裂分析与探讨[J]. 岩土力学，2008，29(8)：2 121–2 125.(LI Zongli，REN Qingwen. Analysis and discussion on rock and concrete material hydraulic fracturing under natural power[J]. Rock and Soil Mechanics，2008，29(8)：2 121–2 125.(in Chinese))
[15] 李宗利，张宏朝，任青文，等. 岩石裂纹水力劈裂分析与临界水压计算[J]. 岩土力学，2005，26(8)：1 216–1 220.(LI Zongli，ZHANG Hongchao，REN Qingwen，et al. Analysis of hydraulic fracturing and calculation of critical internal water pressure of rock fracture[J]. Rock and Soil Mechanics，2005，26(8)：1 216–1 220.(in Chinese))
2012, Vol. 31 
