为指导水力压裂施工,用FDEM-flow方法对多孔水力压裂问题进行了研究。研究结果显示:当H2孔的水压较小时,由H1孔出发的裂缝几乎不朝H2孔偏转;当H2孔的水压较大时,H1孔出发朝下扩展的裂缝,向H2孔偏转明显;当H1,H3孔同步增大水压时,H1出发向下扩展的裂缝朝H3孔偏转,H3孔出发向上扩展的裂缝朝H1孔偏转,最终在H1孔和H3孔间形成2条相向扩展的裂缝。上述研究结果表明:水力压裂裂缝的走向会受到相邻孔的干涉,可以通过相邻孔应力干扰控制压裂裂缝的走向;同时相邻孔的干涉,可以降低注水孔的起裂水压力,这也从侧面说明了同步压裂技术的合理性。
Abstract
In order to instruct construction of hydraulic fracturing, with the proposed FDEM-flow method, we studied multi-hole hydraulic fracturing. When the pressure of hole H2 is small, crack starting from hole H1 hardly deflects toward hole H2; when water pressure of H2 is large, crack starting from H1 propagates to H2 obviously; while when pressures of H1 and H3 increase synchronously, crack extended downward from hole H1 deflects towards hole H3, and crack starting from hole H3 develops towards hole H1, and finally, two opposing propagation cracks form between H1 and H3. Results show that, direction of hydraulic fracturing cracks will be interfered by adjacent holes, hence the direction can be controlled through adjusting the pressure of adjacent holes; while the initiation water pressure that crack begins to occur can be reduced through the adjacent interference, which validated the rationality of synchronous hydraulic fracturing technology.
关键词
FEMDEM /
FDEM-flow /
多孔水力压裂 /
同步压裂 /
裂缝 /
应力干扰
Key words
FEMDEM /
FDEM-flow /
multi-hole hydraulic fracturing /
synchronous fracturing /
fracture /
stress interference
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 张宏学 ,刘卫群. 页岩气开采的相关实验、模型和环境效应[J]. 岩土力学, 2014,35(S2): 85-100.
[2] 韩晓玉, 黄孝泉, 李永松,等. 乌东德水电工程河谷地应力场分布规律[J]. raybet体育在线
院报, 2015(11):34-39.
[3] 赵国平, 陈文华, 马 鹏,等. 水压致裂法地应力测试在水电工程中的应用[J]. raybet体育在线
院报, 2013, 30(11):77-82.
[4] 唐 颖, 张金川, 张 琴,等. 页岩气井水力压裂技术及其应用分析[J]. 天然气工业, 2010, (10):33-38.
[5] 崔 青. 美国页岩气压裂增产技术[J]. 石油化工应用, 2010, (10):1-3.
[6] 侯明勋,王德新,王水林,等. 同时压裂条件下实现井间连通方法探讨[J]. 岩土力学, 2003,24(4): 561-564.
[7] 陈守雨, 杜林麟, 贾碧霞,等. 多井同步体积压裂技术研究[J]. 石油钻采工艺, 2011, (6):59-65.
[8] 李玉伟, 艾 池, 张博文,等. 同步体积压裂对井间裂缝特性的影响[J]. 断块油气田, 2013, 20(6):779-782,DOI:10.6056/dkyqt201306025.
[9] 杨天鸿, 唐春安, 朱万成,等.岩石破裂过程渗流与应力耦合分析[J].岩土工程学报, 2001,23(4): 489-493.
[10]李连崇, 唐春安, 杨天鸿,等. FSD耦合模型在多孔水压致裂试验中的应用[J]. 岩石力学与工程学报, 2004, (19):3240-3244.
[11]李连崇,杨天鸿,唐春安,等. 岩石水压致裂过程的耦合分析[J].岩石力学与工程学报,2004,22(7):1060-1066.
[12]李连崇 ,李 根 ,孟庆民,等. 砂砾岩水力压裂裂缝扩展规律的数值模拟分析[J]. 岩土力学, 2013,34(5): 1501-1507.
[13]Itasca Consulting Group Ltd. User Manual of PFC Code[K]. Minneapolis, USA: Itasca Consulting Group Ltd., 2011.
[14]AL-BUSAIDI A, HAZZARD J F, YOUNG R P. Distinct Element Modeling of Hydraulically Fractured Lac du Bonnet Granite[J]. Journal of Geophysical Research: Solid Earth, 2005, 110(B6): 1-14.
[15]MUNJIZA A. The Combined Finite-discrete Element Method[M]. London: John Wiley & Sons, Ltd., 2004: 29-32.
[16]严成增,郑 宏, 孙冠华,等. 模拟水压致裂的二维FDEM-flow方法[J].岩石力学与工程学报, 2015,34(1):67-75.
[17]严成增,郑 宏,孙冠华,等. 基于FDEM-flow研究地应力对水力压裂的影响. 岩土力学 2016, 37(1): 237-246.
[18]严成增,孙冠华,郑 宏,等. 二维FEM/DEM爆炸气体驱动下的岩体破裂. 岩土力学 2015, 36(8): 2419-2425.
[19]BRUNO M S. Pore Pressure Influence on Tensile Fracture Propagation in Sedimentary Rock[J]. International Journal of Rock Mechanics and Mining Science & Geomechanics Abstracts, 1991, 28(4):261-273.
基金
中国博士后科学基金面上项目(2015M580953);国家重点基础研究发展计划(973)项目(2011CB013505, 2014CB047100)
PDF(1795 KB)
