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Coal Geology & Exploration

Abstract

In order to investigate the rupture process and acoustic emission characteristics of shale under fluid-solid coupling, the numerical simulation of fluid-solid coupling of the Niutitang Formation shale in different bedding angle in the northern part of the Qianbei area was carried out by RFPA2D-Flow numerical software. Studies have shown that due to the influence of the bedding structure, the compressive strength and elastic modulus of shale show obvious anisotropy. The rupture process of shale can be divided into three stages: elasticity, yielding and destruction. With the change of the bedding angle, the shale finally showed three failure modes, namely oblique I, V and flame. Shale with different bedding dips has different evolutionary rules of acoustic emission signals in the process of fracture. For samples with low bedding angles(0°, 15°, 30°), the cumulative AE curve shows a change pattern of “smooth-linear-step-smooth”. The cumulative AE curve of the high-rise dip angle(60°, 75°, 90°) shows a change pattern of “smooth-linear-steep increase”. When =45°, the cumulative AE curve shows a change pattern of “smooth-linear-boost-gradual-boost”, and its AE count shows two p

Keywords

shale, rupture process, fluid-solid coupling, acoustic emission, anisotropy

DOI

10.3969/j.issn.10011986.2020.01.014

Reference

[1] 郭曼,李贤庆,张明扬,等. 黔北地区牛蹄塘组页岩气成藏条件及有利区评价[J]. 煤田地质与勘探,2015,43(2):37-43. GUO Man,LI Xianqing,ZHANG Mingyang,et al. Reservoir-forming conditions and evaluation of favorable area of shale gas in Niutitang Formation in northern Guizhou[J]. Coal Geology & Exploration,2015,43(2):37-43.

[2] CHANG Yuan,HUANG Runze,RIES ROBERT J,et al.Life-cycle comparison of greenhouse gas emissions and water consumption for coal and shale gas fired power generation in China[J]. Energy,2015,86:335-343.

[3] 李希建,尹鑫,李维维,等. 贵州牛蹄塘组页岩气表面自由能研究[J]. 煤田地质与勘探,2019,47(1):105-110. LI Xijian,YIN Xin,LI Weiwei,et al. Surface free energy of shale gas in Niutitang Formation in Guizhou Province[J]. Coal Geology & Exploration,2019,47(1):105-110.

[4] WU Zhonghu,ZUO Yujun,WANG Shanyong,et al. Numerical study of multi-period palaeotectonic stress fields in Lower Cambrian shale reservoirs and the prediction of fractures distribution:A case study of the Niutitang Formation in Fenggang No.3 block,south China[J]. Marine and Petroleum Geology,2017,80:369-381.

[5] 雷梦,梁利喜,熊键,等. 硬脆性页岩基础物性实验及井壁稳定性分析[J]. 科学技术与工程,2015,15(7):34-40. LEI Meng,LIANG Lixi,XIONG Jian,et al. Experiment of the fundamental physical properties and analysis of the wellbore stability on hard brittle shale[J]. Science Technology and Engineering,2015,15(7):34-40.

[6] 徐红卫,李贤庆,周宝刚,等. 鄂尔多斯盆地延长探区陆相页岩气储层特征[J]. 煤田地质与勘探,2017,45(6):46-53. XU Hongwei,LI Xianqing,ZHOU Baogang,et al. Characteristics of terrestrial shale gas reservoir in Yanchang exploration area of Ordos basin[J]. Coal Geology & Exploration,2017,45(6):46-53.

[7] 唐颖,唐玄,王广源,等. 页岩气开发水力压裂技术综述[J]. 地质通报,2011,30(2):393-399. TANG Ying,TANG Xuan,WANG Guangyuan,et al. Summary of hydraulic fracturing technology in shale gas development[J]. Geological Bulletin of China,2011,30(2):393-399.

[8] 衡帅,杨春和,郭印同,等. 层理对页岩水力裂缝扩展的影响研究[J]. 岩石力学与工程学报,2015,34(2):228-237. HENG Shuai,YANG Chunhe,GUO Yintong,et al. Influence of bedding planes on hydraulic fracture propagation in shale formations[J]. Chinese Journal of Rock Mechanics and Engineering,2015,34(2):228-237.

[9] HU Jinghong,YANG Shigang,FU Daoming,et al. Rock mechanics of shear rupture in shale gas reservoirs[J]. Journal of Natural Gas Science and Engineering,2016,36:943-949.

[10] NIANDOU H,SHAO J F,HENRY J P,et al. Laboratory investigation of the mechanical behaviour of Tournemire shale[J]. International Journal of Rock Mechanics and Mining Sciences,1997,34:3-16.

[11] VALÈS F,MINH D N,GHARBI H,et al. Experimental study of the influence of the degree of saturation on physical and mechanical properties in Tournemire shale(France)[J]. Applied Clay Science,2004,26(1/2/3/4):197-207.

[12] CHEN Ping,HAN Qiang,MA Tianshou,et al. The mechanical properties of shale based on micro-indentation test[J]. Petroleum Exploration and Development,2015,42(5):723-732.

[13] QIAO Lyu,LONG Xinping,RANJITH P G,et al. Experimental investigation on the mechanical properties of a low-clay shale with different adsorption times in sub-/super-critical CO2[J]. Energy,2018,147:1288-1298.

[14] 杨志鹏,何柏,谢凌志,等. 基于巴西劈裂试验的页岩强度与破坏模式研究[J]. 岩土力学,2015,36(12):3447-3455. YANG Zhipeng,HE Bai,XIE Lingzhi,et al. Strength and failure modes of shale based on Brazilian test[J]. Rock and Soil Mechanics,2015,36(12):3447-3455.

[15] 侯振坤,杨春和,郭印同,等. 单轴压缩下龙马溪组页岩各向异性特征研究[J]. 岩土力学,2015,36(9):2541-2550. HOU Zhenkun,YANG Chunhe,GUO Yintong,et al. Experimental study on anisotropic properties of Longmaxi Formation shale under uniaxial compression[J]. Rock and Soil Mechanics,2015,36(9):2541-2550.

[16] 衡帅,杨春和,郭印同,等. 层理对页岩水力裂缝扩展的影响研究[J]. 岩石力学与工程学报,2015,34(2):228-237. HENG Shuai,YANG Chunhe,GUO Yintong,et al. Influence of bedding planes on hydraulic fracture propagation in shale formations[J]. Chinese Journal of Rock Mechanics and Engineering,2015,34(2):228-237.

[17] 魏元龙,杨春和,郭印同,等. 单轴循环荷载下含天然裂隙脆性页岩变形及破裂特征试验研究[J]. 岩土力学,2015,36(6):1649-1658. WEI Yuanlong,YANG Chunhe,GUO Yintong,et al. Experimental investigation on deformation and fracture characteristics of brittle shale with natural cracks under uniaxial cyclic loading[J]. Rock and Soil Mechanics,2015,36(6):1649-1658.

[18] CHEN Dong,PAN Zhejun,YE Zhihui. Dependence of gas shale fracture permeability on effective stress and reservoir pressure:Model match and insights[J]. Fuel,2015,139:383-392.

[19] WU Zhonghu,ZUO Yujun,WANG Shanyong,et al. Experimental study on the stress sensitivity and influence factors of shale under varying stress[J]. Shock and Vibration,2018,Article ID:3616942.

[20] 张宏学,刘卫群,朱立. 页岩储层裂隙渗透率模型和试验研究[J]. 岩土力学,2015,36(3):719-729. ZHANG Hongxue,LIU Weiqun,ZHU Li. Fracture permeability model and experiments of shale gas reservoirs[J]. Rock and Soil Mechanics,2015,36(3):719-729.

[21] 杨天鸿,唐春安,李连崇,等. 非均匀岩石破裂过程渗透率演化规律研究[J]. 岩石力学与工程学报,2004,23(5):758-762. YANG Tianhong,TANG Chun'an,LI Lianchong,et al. Study on permeability evolution in failure process of in homogeneous rock[J]. Chinese Journal of Rock Mechanics and Engineering,2004,23(5):758-762.

[22] 杨天鸿,唐春安,梁正召,等. 脆性岩石破裂过程损伤与渗流耦合数值模型研究[J]. 力学学报,2003,35(5):533-541. YANG Tianhong,TANG Chun'an,LIANG Zhengzhao,et al. Study on model of damage and flow coupling in brittle rock failure process[J]. Chinese Journal of Theoretical and Applied Mechanics,2003,35(5):533-541.

[23] WU Zhonghu,ZUO Yujun,WANG Shanyong,et al. Numerical simulation and fractal analysis of mesoscopic scale failure in shale using digital images[J]. Journal of Petroleum Science and Engineering,2016,145:592-599.

[24] 左宇军,孙文吉斌,邬忠虎,等. 渗透压-应力耦合作用下页岩渗透性试验[J]. 岩土力学,2018,39(9):3253-3260. ZUO Yujun,SUN Wenjibin,WU Zhonghu,et al. Experiment on permeability of shale under osmotic pressure and stress coupling[J]. Rock and Soil Mechanics,2018,39(9):3253-3260.

[25] 王晓雷. 软岩层理结构效应实验研究[D]. 北京:中国矿业大学(北京),2013. WANG Xiaolei. Experimental study on bedding structure effect of soft rock[D]. Beijing:China University of Mining & Technology(Beijing),2013.

[26] 梁正召,唐春安,唐世斌,等. 岩石损伤破坏过程中分形与逾渗演化特征[J]. 岩土工程学报,2007,29(9):1386-1391. LIANG Zhengzhao,TANG Chun'an,TANG Shibin,et al. Characteristics of fractal and percolation of rocks subjected to uniaxial compression during their failure process[J]. Chinese Journal of Geotechnical Engineering,2007,29(9):1386-1391.

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