浸泡作用下砂岩断裂力学特性及劣化机理

邓华锋; 原先凡; 李建林; 罗骞; 何明

doi:10.3799/dqkx.2014.011

浸泡作用下砂岩断裂力学特性及劣化机理

doi: 10.3799/dqkx.2014.011

邓华锋^{1, 2,},
原先凡^{1, 2},
李建林^{1, 2},
罗骞^{1, 2},
何明^{1, 2}

1.
三峡地区地质灾害与生态环境湖北省协同创新中心, 湖北宜昌 443002
2.
三峡大学三峡库区地质灾害教育部重点实验室, 湖北宜昌 443002

基金项目:

"973"计划前期研究专项课题 2012CB426502

国家自然科学基金资助项目 51309141

湖北省自然科学基金资助项目 2012FFB03805

三峡大学土木与建筑学院优秀硕士学位论文培育项目资助 PY201314

详细信息

作者简介:
邓华锋(1979-), 男, 副教授, 博士, 主要从事岩土工程方面的教学与研究工作.E-mail: dhf8010@ctgu.edu.cn

中图分类号: TU443
计量
- 文章访问数: 3045
- HTML全文浏览量: 597
- PDF下载量: 397
- 被引次数: 0
出版历程
- 收稿日期: 2013-06-21
- 刊出日期: 2014-01-01

Fracture Mechanics Characteristics and Deterioration Mechanism of Sandstone under Reservoir Immersion Interaction

Deng Huafeng^{1, 2
,},
Yuan Xianfan^{1, 2},
Li Jianlin^{1, 2},
Luo Qian^{1, 2},
He Ming^{1, 2}

1.
Collaborative Innovation Center for Geo-Hazards and Eco-Environment in Three Gorges Area, Yichang 443002, China
2.
Key Laboratory of Geological Hazards on Three Gorges Reservoir Area of Ministry of Education, China Three Gorges University, Yichang 443002, China

摘要

摘要: 岩石的断裂韧度对于定量评价工程的安全及稳定具有重要意义, 而岩石的破坏常常有水参与, 在库水长期浸泡作用下, 岩石的断裂力学特性将如何变化值得深入研究.基于此, 以库岸边坡典型砂岩为研究对象, 设计了长期浸泡试验, 并基于断裂韧度、变形破坏特征和微观结构变化进行综合分析.试验结果表明: (1)浸泡作用下, 砂岩的断裂韧度具有明显的劣化趋势, 而且劣化幅度有一个先增大后减小的趋势, 浸泡5~6月后, 劣化趋势逐渐减缓；(2)砂岩三点弯曲试验的P-CMOD关系曲线可以比较明显地分成3个阶段: 弹性阶段、屈服阶段、裂纹开展及破坏阶段, 随着浸泡时间的增长, 弹性阶段逐渐变短, 屈服阶段逐渐变长, 裂纹开展阶段曲线下降趋势逐渐变缓, 而且达到开裂峰值荷载对应的切口张开位移逐渐增大, 砂岩有逐渐“变软”趋势, 脆性逐渐减弱, 塑性逐渐增强；(3)浸泡作用导致的润滑、软化和砂岩内部微观结构的变化, 特别是微观裂纹、裂隙的发展是导致砂岩断裂韧度及其他力学参数劣化的根本原因.研究成果对于把握库水长期浸泡作用下砂岩断裂力学特性具有比较重要的参考价值.
- 长期浸泡 /
- 水-岩作用 /
- 三点弯曲 /
- 断裂韧度 /
- 工程地质
Abstract: The fracture toughness of rock is of great significance in quantitative evaluation of engineering safety and stability. Rocks often destruct with water, so it is worthwhile to do study on the issue as how the rock fracture toughness and associated mechanical parameters change under long-term immersion of reservoir water. In this paper, a long-term immersion test is designed and carried out and a comprehensive analysis is done in aspects such as the fracture toughness, deformation failure characteristics and microstructure change characteristics. The results show that: (1) under the water-rock interaction, the fracture toughness has a significant deterioration trend, and the deterioration rate increased in prophase and lowered in anaphase; and the deterioration rate gradually becomes slow after 5 or 6 months' immersion. (2) The P-CMOD relation curves of the sandstone three-point bending test can be divided into three stages, namely elastic stage, yield stage, and crack development and damage phases; and with the immersion time, the elastic stage gradually becomes shorter, the yield stage gradually becomes longer, and the downward trend of crack development phase gradually becomes slow, meanwhile, the incision opening displacement which is corresponding to cracking peak load gradually increases. The sandstone brittleness gradually weakens, and plasticity gradually enhances. (3) Lubrication, softening and changes of sandstone's inner microscopic structure caused by water-rock interaction, especially the micro-cracks and the development of the cracks are the basic reasons which lead to the deterioration of the sandstone fracture toughness and other mechanical parameters. The research results facilitate the understanding of the degradation law of sandstone fracture toughness under long-term reservoir water immersion.
- long-term immersion /
- water-rock interaction /
- three-point bending /
- fracture toughness /
- engineering geology

HTML全文

图 1 典型三点弯曲试样

Fig. 1. Typical three-point bending sandstone samples

下载: 全尺寸图片幻灯片

图 2 浸泡作用下砂岩断裂韧度劣化曲线

Fig. 2. Deterioration curves of fracture toughness of sandstone under immersion interaction

下载: 全尺寸图片幻灯片

图 3 单次作用下砂岩断裂韧度劣化百分比

Fig. 3. Deterioration percentage of fracture toughness under single-time immersion interaction

下载: 全尺寸图片幻灯片

图 4 断裂韧度与纵波波速关系

Fig. 4. The relation graph of fracture toughness and longitudinal wave velocity

下载: 全尺寸图片幻灯片

图 5 典型试样P-CMOD关系曲线

Fig. 5. Typical P-CMOD curves of sandstone samples

下载: 全尺寸图片幻灯片

图 6 砂岩试样典型微观照片(400×)

a.初始状态；b.浸泡3个月时的状态；c.浸泡6个月时的状态

Fig. 6. Microscopic-structure photographs of typical sandstone samples

下载: 全尺寸图片幻灯片

表 1 断裂韧度K_IC试验结果

Table 1. Fracture toughness K_IC testing value

时间(月)	K_IC(MPa·m^1/2)	K_IC均值(MPa·m^1/2)	峰值荷载对应切口张开位移(mm)	纵波波速(m/s)
0	0.440	0.46	0.069	3 292
	0.490		0.065	3 318
	0.473		0.068	3 296
	0.437		0.071	3 180
1	0.473	0.45	0.070	3 284
	0.437		0.071	3 286
	0.461		0.071	3 344
	0.437		0.075	3 255
2	0.398	0.43	0.075	2 895
	0.445		0.074	3 141
	0.432		0.072	3 273
	0.208		0.088	2 738
3	0.341	0.39	0.078	2 811
	0.424		0.088	2 962
	0.424		0.082	3 236
	0.374		0.086	2 995
4	0.398	0.38	0.085	2 911
	0.390		0.095	2 895
	0.422		0.088	3 092
	0.328		0.093	2 758
5	0.336	0.35	0.103	2 805
	0.381		0.094	3 012
	0.324		0.090	2 705
	0.365		0.095	2 819
6	0.345	0.33	0.103	2 768
	0.328		0.098	2 611
	0.312		0.097	2 629
	0.347		0.101	2 806

下载: 导出CSV

表 2 pH值和离子浓度检测结果

Table 2. The detection results of pH value and ion concentration

浸泡时间(月)	pH值	离子浓度(mg/L)
浸泡时间(月)	pH值	Ca²⁺	Na⁺	K⁺
初始	7.26	43.30	16.45	3.17
1	7.51	50.88	18.57	3.48
2	7.75	53.52	20.78	3.79
3	7.94	54.01	22.40	4.04
4	8.11	55.43	23.39	4.17
5	8.27	56.10	24.48	4.26
6	8.29	56.68	24.84	4.28

下载: 导出CSV

参考文献(49)

Cao, P., Yang, H., Jiang, X.L., et al., 2010. Subcritical Crack Growth of Rock during Water-Rock Interaction. Journal of Central South University (Science and Technology), 41(2): 649-654(in Chinese with English abstract). http://www.researchgate.net/publication/289282506_Subcritical_crack_growth_of_rock_during_water-rock_interaction
Ciccotti, M., Gonzato, G., Mulargia, F., 2000. The Double Torsion Loading Configuration for Fracture Propagation: An Improved Methodology for the Load-Relaxation at Constant Displacement. International Journal of Rock Mechanics and Mining Sciences, 37(7): 1103-1113. doi: 10.1016/S1365-1609(00)00045-9
Cui, Z.D., Liu, D.A., An, G.M., et al., 2010. Research for Determining Mode I Rock Fracture Toughness K_IC Using Cracked Chevron Notched Brazilian Disc Specimen. Rock and Soil Mechanics, 31(9): 2743-2748 (in Chinese with English abstract).
Deng, H.F., 2010. Study on the Mechanism and Effects of Water-Rock Interaction under Water Level Change Region (Dissertation). Wuhan University, Wuhan (in Chinese with English abstract).
Deng, H.F., Li, J.L., Deng, C.J., et al., 2011. Analysis of Sampling in Rock Mechanics Test and Compressive Strength Prediction Methods. Rock and Soil Mechanics, 32(11): 3399-3403 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YTLX201111035.htm
Deng, H.F., Li, J.L., Deng, C.L., et al., 2012. Research on Secondary Porosity Changing Law of Sandstone under Saturation-Air Dry Cycles. Rock and Soil Mechanics, 33(2): 483-488 (in Chinese with English abstract). http://www.cqvip.com/QK/94551X/201202/40782379.html
Feng, X.T., Li, S.J., Chen, S.L., 2004. Effect of Water Chemical Corrosion on Strength and Cracking Characteristics of Rocks-A Review. Key Engineering Materials, 261-263(Ⅱ): 1355-1360. doi: 10.4028/www.scientific.net/KEM.261-263.1355
Freiman, S.W., 1982. Effects of Chemical Environments on Slow Crack Growth in Glasses and Ceramics. Journal of Geophysical Research, 89(B6): 4072-4076. doi: 10.1029/JB089iB06p04072
Gao, Y., Gong, N.P., Luo, Y.F., 2012. Experimental Study on Dynamic Fracture Toughness of Rock. Journal of Anhui University of Science and Technology (Natural Science), 32(1): 13-16 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTotal-HLGB201201004.htm
Laijtai, E.Z., Schmidtke, R.H., Bielus, L.P., 1987. Effect of Water on the Time-Dependent Deformation and Fracture of a Granite. Int. J. Rock Mech. Min. Sci. Geomech. Abstr., 24(4): 247-255. doi: 10.1016/0148-9062(87)90179-3
Lau, J.S.O., Jackson, R., Gorski, B., et al., 1991. Effects of Temperature and Pressure on the Mechanical Properties of Lac du Bonnet Grey Granite. In: Balkema, A.A., ed., The 32nd U.S. Symposium on Rock Mechanics(USRMS). American Rock Mechanics Association, Norman.
Li, N., Zhu, Y.M., Su, B., et al., 2003. A Chemical Damage Model of Sandstone in Acid Solution. International Journal of Rock Mechanics and Mining Sciences, 40(2): 243-249. doi: 10.1016/S1365-1609(02)00132-6
Li, W.G., Zhang, X.P., Zhong, Y.M., 2005. Formation Mechanism of Secondary Dissolved Pores in Arose. Oil & Gas Geology, 26(2): 220-223 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-SYYT200502015.htm
Liang, X.J., 1995. Water Rock Interaction and the Ore-Forming Material Sources. Macmillan Press, Beijing (in Chinese).
Liu, T.Y., Cao, P., Zhang, L.F., et al., 2012. Study of Fracture Damage Evolution Mechanism of Compression-Shear Rock Cracks under High Seepage Pressure. Rock and Soil Mechanics, 33(6): 1801-1808 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YTLX201206030.htm
Liu, X.R., Fu, Y., Wang, Y.X., et al., 2008. Deterioration Rules of Shear Strength of Sand Rock under Water-Rock Interaction of Reservoir. Chinese Journal of Geotechnical Engineering, 30(9): 1298-1302 (in Chinese with English abstract). http://www.cnki.com.cn/Article/CJFDTotal-YTGC200809008.htm
Ni, M., Wang, K., Wang, Q.Z., 2010. Experimental Study on Mixed-Mode Dynamic Fracture of Four Rocks under Impact Loading Using Split Hopkinson Pressure Bar. Chinese Journal of Applied Mechanics, 27(4): 697-702 (in Chinese with English abstract). http://www.researchgate.net/publication/286303936_Experimental_study_on_mixed-mode_dynamic_fracture_of_four_rocks_under_impact_loading_using_split_Hopkinson_pressure_bar
Saadaoui, M., Reynaud, P., Fantozzi, G., et al., 2000. Slow Crack Growth Study of Plaster Using the Double Torsion Method. Ceramics International, 26(4): 435-439. doi: 10.1016/S0272-8842(99)00078-4
Shen, Z.L., Wang, Y.X., Guo, H.M., 2012. Opportunities and Challenges of Water-Rock Interaction Studies. Earth Science-Journal of China University of Geosciences, 37(2): 207-219(in Chinese with English abstract). http://www.researchgate.net/publication/285955958_Opportunities_and_challenges_of_water-rock_interaction_studies
Tang, L.S., Zhang, P.C., Wang, S.J., 2002. Testing Study on Effects of Chemical Action of Aqueous Solution on Crack Propagation in Rock. Chinese Journal of Rock Mechanics and Engineering, 21(6): 822-827(in Chinese with English abstract). http://www.researchgate.net/publication/290488553_Testing_study_on_effects_of_chemical_action_of_aqueous_solution_on_crack_propagation_in_rock
The Professional Standard Compilation Group of People's Republic of China, 2001. Specifications for Rock Tests in Water Conservancy and Hydroelectric Engineering(SL264-2001). China Water Power Press, Beijing (in Chinese).
Tu, G.C., Lu, H.Z., Hong, Y.T., 2000. The Higher Geochemical. Science Press, Beijing (in Chinese).
Wang, Y.X., Cao, P., Huang, Y.H., et al., 2010. Time-Dependence of Damage and Fracture Effect for Strain Softening of Soft Rock under Water Corrosion. Journal of Sichuan University(Engineering Science), 42(4): 55-62 (in Chinese with English abstract). http://www.researchgate.net/publication/287469203_Time-dependence_of_damage_and_fracture_effect_for_strain_softening_of_soft_rock_under_water_corrosion
Xu, Z.M., Huang, R.Q., Yang, L.Z., 2004. Some Problems on Chemical Water-Rock Interaction in Slopes. Chinese Journal of Rock Mechanics and Engineering, 23(16): 2778-2787 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YSLX200416022.htm
Yu, X.Z., 1991. Rock and Concrete Fracture Mechanics. Press of Central South Technology University, Changsha (in Chinese).
Zhu, F.X., Zhou, C.Y., 2009. Forming Mechanism of Dissipative Structure in the Softening Process of Saturated Soft Rocks. Earth Science-Journal of China University of Geosciences, 34(3): 525-532(in Chinese with English abstract). doi: 10.3799/dqkx.2009.058
Zhu, H.H., Yan, Z.G., Deng, T., et al., 2006. Testing Study on Mechanical Properties of Tuff, Granite and Breccia after High Temperatures. Chinese Journal of Rock Mechanics and Engineering, 25(10): 1945-1950 (in Chinese with English abstract). http://www.researchgate.net/publication/279550353_Testing_study_on_mechanical_properties_of_tuff_granite_and_breccia_after_high_temperatures
Zuo, J.P., Xie, H.P., Liu, Y.J., et al., 2010. Investigation on Fracture Characteristics of Sandstone after Thermal Effects through Three-Bending Point Experiments. Chinese Journal of Solid Mechanics, 31(2): 119-126 (in Chinese with English abstract). http://d.wanfangdata.com.cn/periodical/gtlxxb201002002
曹平, 杨慧, 江学良, 等, 2010. 水岩作用下岩石亚临界裂纹的扩展规律. 中南大学学报(自然科学版), 41(2): 649-654. https://www.cnki.com.cn/Article/CJFDTOTAL-ZNGD201002046.htm
崔振东, 刘大安, 安光明, 等, 2010. V形切槽巴西圆盘法测定岩石断裂韧度K_IC的实验研究. 岩土力学, 31(9): 2743-2748. doi: 10.3969/j.issn.1000-7598.2010.09.009
邓华锋, 2010. 库水变幅带水-岩作用机制和作用效应研究(博士学位论文). 武汉: 武汉大学.
邓华锋, 李建林, 邓成进, 等, 2011. 岩石力学试验中试样选择和抗压强度预测方法研究. 岩土力学, 32(11): 3399-3403. doi: 10.3969/j.issn.1000-7598.2011.11.032
邓华锋, 李建林, 邓成进, 等, 2012. "饱和-风干"循环过程中砂岩次生孔隙率变化规律研究. 岩土力学, 33(2): 483-488. doi: 10.3969/j.issn.1000-7598.2012.02.026
高远, 宫能平, 罗裕繁, 2012. 岩石材料动态断裂韧性的实验研究. 安徽理工大学学报(自然科学版), 32(1): 13-16. doi: 10.3969/j.issn.1672-1098.2012.01.003
李汶国, 张晓鹏, 钟玉梅, 2005. 长石砂岩次生溶孔的形成机理. 石油与天然气地质, 26(2): 220-223. doi: 10.3321/j.issn:0253-9985.2005.02.016
梁祥济, 1995. 水-岩相互作用和成矿物质来源. 北京: 学苑出版社.
刘涛影, 曹平, 章立峰, 等, 2012. 高渗压条件下压剪岩石裂纹断裂损伤演化机制研究. 岩土力学, 33(6): 1801-1808. doi: 10.3969/j.issn.1000-7598.2012.06.031
刘新荣, 傅晏, 王永新, 等, 2008. (库)水-岩作用下砂岩抗剪强度劣化规律的试验研究. 岩土工程学报, 30(9): 1298-1302. doi: 10.3321/j.issn:1000-4548.2008.09.006
倪敏, 汪坤, 王启智, 2010. SHPB冲击加载下四种岩石的复合型动态断裂实验研究. 应用力学学报, 27(4): 697-702. https://www.cnki.com.cn/Article/CJFDTOTAL-YYLX201004013.htm
沈照理, 王焰新, 郭华明, 2012. 水-岩相互作用研究的机遇与挑战. 地球科学—中国地质大学学报, 37(2): 207-219. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX201202004.htm
汤连生, 张鹏程, 王思敬, 2002. 水-岩化学作用之岩石断裂力学效应的试验研究. 岩石力学与工程学报, 21(6): 822-827. doi: 10.3321/j.issn:1000-6915.2002.06.012
中华人民共和国行业标准编写组, 2001. 水利水电工程岩石试验规程(SL264-2001). 北京: 中国水利水电出版社.
涂光炽, 卢焕章, 洪业汤, 2000. 高等地球化学. 北京: 科学出版社.
汪亦显, 曹平, 黄永恒, 等, 2010. 水作用下软岩软化与损伤断裂效应的时间相依性. 四川大学学报(工程科学版), 42(4): 55-62. https://www.cnki.com.cn/Article/CJFDTOTAL-SCLH201004012.htm
徐则民, 黄润秋, 杨立中, 2004. 斜坡水-岩化学作用问题. 岩石力学与工程学报, 23(16): 2778-2787. doi: 10.3321/j.issn:1000-6915.2004.16.022
于骁中, 1991. 岩石和混凝土断裂力学. 长沙: 中南工业大学出版社.
朱凤贤, 周翠英, 2009. 软岩遇水软化的耗散结构形成机制. 地球科学—中国地质大学学报, 34(3): 525-532. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX200903017.htm
朱合华, 闫治国, 邓涛, 等, 2006.3种岩石高温后力学性质的试验研究. 岩石力学与工程学报, 25(10): 1945-1950. doi: 10.3321/j.issn:1000-6915.2006.10.001
左建平, 谢和平, 刘瑜杰, 等, 2010. 不同温度热处理后砂岩三点弯曲的断裂特性. 固体力学学报, 31(2): 119-126. https://www.cnki.com.cn/Article/CJFDTOTAL-GTLX201002003.htm