Uniaxial compression damage and crack propagation features of parallel double-fissure sandstones under high-humidity environments
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摘要: 深部裂隙矿柱长期受高湿环境中水分子所侵蚀,其化学动力过程与矿房稳定性及控制地表沉降密切相关。对预制平行双裂隙标准砂岩试样进行了单轴压缩试验,研究高湿对裂隙砂岩强度变形特性、裂纹演化以及破坏模式的影响,结合电镜扫描和XRD衍射,分析了试件在高湿环境水化作用前后的微细观结构变化和质量损失特征。结果表明：①试样结构疏松程度与湿度成正相关,湿度升高,试样表观致密结构变得松散并伴有次生孔隙发育,形成模糊的层间界面,且微裂隙数目增加,质量损失率加剧。②裂隙砂岩在单轴压缩下主要有拉伸破坏,剪切破坏和二者混合型破坏。裂纹萌生的类型主要有翼形裂纹、反抗拉裂纹以及共面/非共面次级裂纹。其裂纹扩展及破坏模式受控于湿度,随着湿度升高,裂纹起裂应力和贯通应力降低,宏观裂纹发育的整体数量呈下降趋势,且其破坏模式由剪切破坏过渡到拉伸破坏。③高湿环境对裂隙砂岩产生水岩化学作用,减弱了裂隙结构面以及矿物颗粒间的摩擦作用,降低了其峰值强度,峰值应变和弹性模量,提高了泊松比,加速了裂隙砂岩的破坏。Abstract: Fractured pillars are eroded by gaseous water under high-humidity environments, and their hydro-chemical processes are closely related to the stability of the mineroom and ground subsidence. The uniaxial compression tests are carried out on standard sandstones with prefabricated parallel double-fissure to analyze the effects of high humidity on the strength-deformation properties, crack evolution and damage modes. By using the electron microscopy scanning and XRD diffraction, the microstructural changes and mass loss characteristics are analyzed before and after hydration. The results show that: (1) The higher humidity causes the structure to loosen more, the interlayer demarcation gets blurred, the number of microcracks grows and the rate of mass loss improves. (2) The damage modes contain tensile, shear and mixed tensile/shear damages. The crack growth includes in 4 types: wing cracks, tensile resistance cracks, and coplanar/non-coplanar secondary cracks. The crack propagation and damage modes are controlled by humidity. As the humidity increases, the crack initiation and penetration stresses drop, the number of cracks sprouting macroscopically reduces and the failure mode changes from shear to tensile failure. (3) The High-humidity condition produces water-rock chemical effects on fractured sandstones, weakening the structural surface of the cracks and the friction between the mineral particles, reducing the peak strength, peak strain and elastic modulus, increasing the Poisson's ratio and accelerating the destruction.
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图 5 砂岩X射线衍射矿物成分分析
Figure 5. Analysis of X-ray diffraction mineral composition of sandstones
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图 6 裂隙砂岩在4种湿度环境下60 d的表观对比图
Figure 6. Apparent comparison of fractured sandstones under 4 kinds of humidity environments for 60 d
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图 7 不同湿度环境下60 d裂隙砂岩表面电镜扫描图
Figure 7. Scanning electron microscopy of surfaces of fractured sandstone under different humidity environments for 60 d
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图 8 3种湿度环境下放置60 d的裂隙砂岩试样的质量变化对比
Figure 8. Comparison of mass changes of fractured sandstone specimens for 60 d under 3 kinds of humidity environments
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图 9 不同湿度环境下60 d双裂隙砂岩试样单轴压缩规律
Figure 9. Uniaxial compression law of double-fissure sandstones under different humidity environments for 60 d
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图 10 不同湿度下60 d对裂隙砂岩弹性模量、泊松比的影响
Figure 10. Effects of different humidity environments for 60 d on modulus of elasticity and Poisson's ratio of fractured sandstones
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图 11 典型试样裂纹扩展与应力-应变曲线对应关系
Figure 11. Relationship between crack growth and stress-strain curve of typical specimens
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图 12 单轴压缩下裂隙试样的裂纹发育图
Figure 12. Crack propagation law of fractured sandstone specimen under uniaxial compression
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图 14 湿度对平行双裂隙砂岩起裂应力的影响
Figure 14. Effects of humidity on initiation stress of fractures in parallel double-fissure sandstones
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图 15 湿度对平行双裂隙砂岩贯通应力的影响
Figure 15. Effects of humidity on penetration stress in parallel double-fissure sandstones
表 1 预制平行双裂隙砂岩试样基本参数
Table 1 Basic parameters of sandstone specimens with prefabricated parallel double-fissure
编号 平均高度/mm 平均直径/mm 平均质量/g 平均密度/(g·cm-3) 控制湿度/% UCS-（1~5） 99.97 49.55 420.63 2.14 干燥 UCS-（6~10） 100.04 49.43 417.77 2.12 80 UCS-（11~ 15） 99.92 49.63 422.57 2.15 90 UCS-（16~ 20） 100.03 49.76 418.07 2.13 100 
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表 2 高湿处理60 d后平行双裂隙砂岩单轴压缩力学参数
Table 2 Mechanical parameters of sandstone with parallel double-fissure under high-humidity environments for 60 d under uniaxial compression
试样编号 控制湿度/% 峰值强度/MPa 弹性模量/GPa 泊松比 试样编号 控制湿度/% 峰值强度/MPa 弹性模量/GPa 泊松比 UCS-1 干燥 25.07 4.81 0.15332 UCS-11 90 16.52 3.02 0.16168 UCS-2 25.09 4.53 0.15541 UCS-12 16.95 2.81 0.16498 UCS-3 23.23 4.93 0.15326 UCS-13 17.26 2.93 0.16126 UCS-4 26.23 4.85 0.15763 UCS-14 18.48 3.09 0.16265 UCS-5 26.09 5.08 0.16348 UCS-15 17.52 3.02 0.16108 UCS-6 80 18.5 3.35 0.15642 UCS-16 100 15.23 3.15 0.17446 UCS-7 20.4 3.21 0.15952 UCS-17 17.52 3.09 0.17387 UCS-8 19.52 3.53 0.15945 UCS-18 17.25 3.13 0.16954 UCS-9 19.23 3.33 0.15983 UCS-19 15.52 3.06 0.16576 UCS-10 19.13 3.18 0.15883 UCS-20 16.44 3.17 0.17442
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[1] 杨圣奇, 戴永浩, 韩立军, 等. 断续预制裂隙脆性大理岩变形破坏特性单轴压缩试验研究[J]. 岩石力学与工程学报, 2009, 28(12): 2391-2404. doi: 10.3321/j.issn:1000-6915.2009.12.003 YANG Sheng-qi, DAI Yong-hao, HAN Li-jun, et al. Uniaxial compression experimental research on deformation and failure properties of brittle marble specimen with pre-existing fissures[J]. Chinese Journal of Rock Mechanics and Engineering, 2009, 28(12): 2391-2404. (in Chinese) doi: 10.3321/j.issn:1000-6915.2009.12.003
[2] 袁媛, 潘鹏志, 赵善坤, 等. 基于数字图像相关法的含填充裂隙大理岩单轴压缩破坏过程研究[J]. 岩石力学与工程学报, 2018, 37(2): 339-351. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201802008.htm YUAN Yuan, PAN Peng-zhi, ZHAO Shan-kun, et al. The failure process of marble with filled crack under uniaxial compression based on digital image correlation[J]. Chinese Journal of Rock Mechanics and Engineering, 2018, 37(2): 339-351. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201802008.htm
[3] BOBET A, EINSTEIN H H. Fracture coalescence in rock-type materials under uniaxial and biaxial compression[J]. International Journal of Rock Mechanics and Mining Sciences, 1998, 35(7): 863-888. doi: 10.1016/S0148-9062(98)00005-9
[4] ZHOU T, ZHU J B, JU Y, et al. Volumetric fracturing behavior of 3D printed artificial rocks containing single and double 3D internal flaws under static uniaxial compression[J]. Engineering Fracture Mechanics, 2019, 205: 190-204. doi: 10.1016/j.engfracmech.2018.11.030
[5] 赵延林, 万文, 王卫军, 等. 类岩石材料有序多裂纹体单轴压缩破断试验与翼形断裂数值模拟[J]. 岩土工程学报, 2013, 35(11): 2097-2109. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201311024.htm ZHAO Yan-lin, WAN Wen, WANG Wei-jun, et al. Fracture experiments on ordered multi-crack body in rock-like materials under uniaxial compression and numerical simulation of wing cracks[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(11): 2097-2109. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201311024.htm
[6] 何满潮. 深部软岩工程的研究进展与挑战[J]. 煤炭学报, 2014, 39(8): 1409-1417. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201408006.htm HE Man-chao. Progress and challenges of soft rock engineering in depth[J]. Journal of China Coal Society, 2014, 39(8): 1409-1417. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201408006.htm
[7] 方晓阳. 21世纪环境岩土工程展望[J]. 岩土工程学报, 2000, 22(1): 1-11. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200001000.htm FANG Xiao-yang. Environmental geotechnology- perspective in the 21st century[J]. Chinese Journal of Geotechnical Engineering, 2000, 22(1): 1-11. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200001000.htm
[8] PANP Z, MIAO S T, JIANG Q, et al. The influence of infilling conditions on flaw surface relative displacement induced cracking behavior in hard rock[J]. Rock Mechanics and Rock Engineering, 2020, 53(10): 4449-4470. doi: 10.1007/s00603-019-02033-x
[9] DUNNING J, DOUGLAS B, MILLER M, et al. The role of the chemical environment in frictional deformation: Stress corrosion cracking and comminution[J]. Pure and Applied Geophysics, 1994, 143(1/2/3): 151-178.
[10] ESTERHUIZEN G S, DOLINAR D R, ELLENBERGER J L. Pillar strength in underground stone mines in the United States[J]. International Journal of Rock Mechanics and Mining Sciences, 2011, 48(1): 42-50.
[11] NARA Y, TANAKA M, HARUI T. Evaluating long-term strength of rock under changing environments from air to water[J]. Engineering Fracture Mechanics, 2017, 178: 201-211.
[12] 陈建生, 李平, 王涛, 等. 青藏高原东缘水库绕坝基渗流化学溶蚀研究[J]. 岩土工程学报, 2019, 41(4): 610-616. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201904003.htm CHEN Jian-sheng, LI Ping, WANG Tao, et al. Chemical dissolution of seepage around dam foundation of a reservoir in eastern margin of the Tibetan Plateau[J]. Chinese Journal of Geotechnical Engineering, 2019, 41(4): 610-616. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201904003.htm
[13] 李二强, 冯吉利, 张龙飞, 等. 水-岩及风化作用下层状炭质板岩巴西劈裂试验研究[J]. 岩土工程学报, 2021, 43(2): 329-337. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC202102017.htm LI Er-qiang, FENG Ji-li, ZHANG Long-fei, et al. Brazilian tests on layered carbonaceous slate under water-rock interaction and weathering[J]. Chinese Journal of Geotechnical Engineering, 2021, 43(2): 329-337. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC202102017.htm
[14] ZHAO Y L, ZHANG L Y, LIAO J, et al. Experimental study of fracture toughness and subcritical crack growth of three rocks under different environments[J]. International Journal of Geomechanics, 2020, 20(8): 0402128.
[15] 工程岩体试验方法标准：GB/T50266—2013[S]. 2013. Standard for Test Methods of Engineering Rock Mass: GB/T 50266—2013[S]. 2013. (in Chinese)
[16] 陈伟, 万文, 谢森林. 岩石力学实验温湿度及酸性环境控制模拟装置及模拟方法: CN210243364U[P]. 2019-08-30. CHEN Wei, WAN Wen, XIE Sen-lin. Rock mechanics experiment temperature, humidity and acid environment control simulation device: CN210243364U[P]. 2019-08-30. (in Chinese)
[17] 刘杰, 李建林, 张玉灯, 等. 宜昌砂岩不同pH值酸性溶液浸泡下时间比尺及强度模型研究[J]. 岩石力学与工程学报, 2010, 29(11): 2319-2327. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201011021.htm LIU Jie, LI Jian-lin, ZHANG Yu-deng, et al. Study of time scale and strength model of Yichang sandstone under different pH values of acidic solution immersion[J]. Chinese Journal of Rock Mechanics and Engineering, 2010, 29(11): 2319-2327. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201011021.htm
[18] 苗胜军, 蔡美峰, 冀东, 等. 酸性化学溶液作用下花岗岩损伤时效特征与机理[J]. 煤炭学报, 2016, 41(5): 1137-1144. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201605011.htm MIAO Sheng-jun, CAI Mei-feng, JI Dong, et al. Aging features and mechanism of Granite's damage under the action of acidic chemical solutions[J]. Journal of China Coal Society, 2016, 41(5): 1137-1144. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201605011.htm
[19] 岩石物理力学性质试验规程：DZ/T0276.25—2015[S]. 2015. Test Procedure for Physical and Mechanical Properties of Rocks: DZ/T0276.25—2015[S]. 2015. (in Chinese)
[20] 杨慧, 曹平, 江学良. 水-岩化学作用等效裂纹扩展细观力学模型[J]. 岩土力学, 2010, 31(7): 2104-2110. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201007015.htm YANG Hui, CAO Ping, JIANG Xue-liang. Micromechanical model for equivalent crack propagation under chemical corrosion of water-rock interaction[J]. Rock and Soil Mechanics, 2010, 31(7): 2104-2110. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201007015.htm
[21] MIAO S T, PAN P Z, WU Z H, et al. Fracture analysis of sandstone with a single filled flaw under uniaxial compression[J]. Engineering Fracture Mechanics, 2018, 204: 319-343.
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