Failure process and long-term stability analysis of typical unstable rock mass in the Three Gorges Reservoir area considering rock mass deterioration
-
摘要:
自三峡库区蓄水以来, 岸坡消落带岩体劣化趋势明显, 加速了岩质岸坡向欠稳定和不稳定发展, 潜在崩塌涌浪灾害威胁长江航道安全。以三峡库区板壁岩为例, 采用抗剪强度折减法分析在岩体劣化工况下危岩体的破坏过程与长期稳定性。结果表明: 在自然工况下, 板壁岩危岩体处于稳定状态; 在库水+岩体劣化工况下, 中部锁固段处拉应力集中, 拉张裂缝逐步向顶部主控裂缝及底部基破碎带延展并相互贯通, 可能发生滑移-剪切破坏; 在库水+岩体劣化+强降雨极端工况下, 约40个水文周期后, 岩体强度下降30%, 板壁岩危岩体的稳定性系数降至约1.14, 处于欠稳定状态, 建议进行工程防治, 提高危岩体稳定性, 以保障航道安全。研究结果可为三峡库区板壁岩及类似危岩体的防灾减灾工作提供科学合理的依据。
Abstract:Since the Three Gorges Reservoir went into service, the rock mass in the hydro-fluctuation belt of the bank slope has obviously deteriorated, which accelerates the instability of the bank slope. The potential debris avalanche threatens the safety of the Yangtze River waterway. The Banbiyan unstable rock mass in the Three Gorges Reservoir area was studied using the shear strength reduction method to analyze the failure process and long-term stability of the unstable rock mass under rock deterioration. The results show that the Banbiyan unstable rock mass is stable under natural working conditions. Under reservoir water and rock mass deterioration, the tensile stress is concentrated at the central section. The tensile cracks gradually penetrate up and down, extending to the prominent controlling cracks at the top and the bottom base fracture zone. Slip-shear failure may occur. Under the condition of reservoir water combined with rock mass deterioration and heavy rainfall, the strength of the rock mass decreases by 30% after about 40 hydrological cycles, and the stability coefficient of the Banbiyan unstable rock mass decreased to about 1.14, which is an under-stable state. It is suggested to carry out engineering prevention and control to improve the stability of dangerous rock mass to ensure the safety of the waterway. The research results can provide a scientific and reasonable basis for disaster prevention and mitigation of the Banbiyan and similar unstable rock masses in the Three Gorges Reservoir area.
-
图 2 板壁岩危岩体破碎带及裂隙分布图
Figure 2. Map showing the fracture zones and fissures in the Banbiyan unstable rock mass
图 3 板壁岩危岩体工程地质剖面图
Figure 3. Engineering geological profile of the Banbiyan unstable rock mass
图 5 W1危岩体边界
a—右边界；b—左边界
Figure 5. Boundary of the W1 unstable rock mass
(a) Right boundary; (b) Left boundary
图 6 基座破碎带特征照片
a—上游危岩体；b—下游危岩体
Figure 6. Field photos showing the features of the foundational fracture zones
(a) Unstable rock mass on the upstream side; (b)Unstable rock mass on the downstream side
图 7 板壁岩危岩体连续-非连续数值模型
Figure 7. Continuous-discontinuous numerical model for the Banbiyan unstable rock mass
图 8 位移及屈服单元云图
a—工况1；b—工况2-1
Figure 8. Cloud diagram showing the displacement and yield element
(a) Under working condition 1; (b) Under working condition 2-1
图 9 塑性区分布过程图(工况2-1)
Figure 9. Diagram showing the extension of the plastic zone (Under working condition 2-1)
图 10 工况2稳定性系数与最大位移量随时间的关系
a—工况2-1；b—工况2-2
Figure 10. Stability coefficient versus maximum displacement as a function of time under working condition 2
(a) Under working condition 2-1; (b) Under working condition 2-2
图 11 位移及屈服单元云图
a—工况3-1；b—工况3-15
Figure 11. Cloud diagram showing the displacement and yield element
(a) Under working condition 3-1;(b) Under working condition 3-15
图 12 工况3稳定性系数与最大位移量随时间的关系
Figure 12. Stability coefficient versus maximum displacement as a function of time under working condition 3
图 13 板壁岩危岩体稳定系数-时间过程曲线
Figure 13. Stability coefficient-time course curves of the Banbiyan unstable rock mass
表 1 板壁岩单体危岩体特征表
Table 1. Characteristics of the Banbiyan unstable rock mass
危岩体编号 是否涉水 整体发育形态 最低基底高程/m 危岩体顶部与基底相对高差/m 破坏方向/(°) 方量/m3 W1 涉水 呈不规则板柱状 ~97 ~162 348 71.78×104 W2 未涉水 呈不规则棱柱体 ~194 ~60 348 1.69×104 W3 未涉水 呈薄板状 ~234 ~23 330 685 
下载: 导出CSV
表 2 板壁岩危岩体灰岩物理力学指标标准值
Table 2. Standard values of physical and mechanical indexes of the limestone from the Banbiyan unstable rock mass
状态 重度/(kN/m3) 弹性模量/×104 MPa 泊松比 抗压强度/MPa 抗拉强度/MPa 黏聚力/MPa 内摩擦角/(°) 灰岩 天然 0.0268 0.69 0.22 21.71 0.46 1.35 37.49 岩体 饱和 0.0269 18.21 0.40 1.08 35.69
下载: 导出CSV
表 3 板壁岩危岩体稳定性系数计算工况
Table 3. Working conditions for calculating the stability coefficient of the Banbiyan unstable rock mass
工况1 工况2 工况3 自然工况 库水+岩体劣化工况 库水+强降雨+岩体劣化工况 1-1：自重+145 m水位
1-2：自重+175 m水位
1-3：自重+175 m水位+强降雨2-1：自重+145 m水位+岩体劣化
2-2：自重+175 m水位+岩体劣化
15个子工况，每个子工况岩体强度下降3%自重+强降雨+175m水位+岩体劣化
15个子工况，每个子工况岩体强度下降3%
下载: 导出CSV
-
DENG C J, WANG K W, YUAN Q S, et al., 2015. Stability of reservoir slope under repetitive variation of reservoir water level[J]. Journal of Yangtze River Scientific Research Institute, 32(4): 96-100. (in Chinese with English abstract) doi: 10.3969/j.issn.1001-5485.2015.04.019 DENG H F, FANG J C, LI J L, et al., 2021. Damage evolution of dynamic characteristics of sandstone under the sequential action of water-rock interaction and cyclic loading and unloading[J]. Rock and Soil Mechanics, 42(2): 343-351. (in Chinese with English abstract) DOCHEZ S, LAOUAFA F, FRANCK C, et al., 2014. Multi-scale analysis of water alteration on the rock slope stability framework[J]. Acta Geophysical, 62(5): 1025-1048. doi: 10.2478/s11600-014-0232-7 FU Y, 2010. Study on water-rock interaction with the cyclic drying-wetting effect on rock[D]. Chongqing: Chongqing University. (in Chinese with English abstract) HU L Y, ZHANG P, HUANG B L, 2022. Long-term deformation and failure mechanism of dangerous rock mass in water-level-fluctuation zone of Three Gorges Reservoir area: a case study of Guanmuling[J/OL]. Journal of Engineering Geology, 1-11. [2022-6-19] https://kns.cnki.net/kcms/detail/detail.aspx?dbcode=CAPJ&dbname=CAPJLAST&filename=GCDZ20221009000&uniplatform=NZKPT&v=9u6_tlouPxa4lAU2YcVmGRdoK6VK6205M_F5Ctg4vW0dyQCGTaZWAUVleKzwiGou. (in Chinese with English abstract) HU M J, ZHANG Z H, YIN Y P, 2021. Study on strength weakening of carbonate rocks with water level fluctuating in Wuxia of three gorges reservoir area[J/OL]. Journal of Engineering Geology, 1-14. [2022-6-19] https://kns.cnki.net/KCMS/detail/detail.aspx?dbcode=CAPJ&dbname=CAPJLAST&filename=GCDZ20210717009. (in Chinese with English abstract) HU Q Z, ZHOU H, XIAO B L, et al., 2010. Analysis of stability of rock bedded slope under hydraulic pressure[J]. Rock and Soil Mechanics, 31(11): 3594-3598. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2010.11.039 HUANG B L, YIN Y P, ZHANG Z H, et al., 2019. Study on deterioration characteristics of shallow rock mass in water the level fluctuation zone of karst bank slopes in Three Gorges Reservoir area[J]. Chinese Journal of Rock Mechanics and Engineering, 38(9): 1786-1796. (in Chinese with English abstract) HUANG B L, YIN Y P, LI B, et al., 2020. Rock mass deterioration and its catastrophic effect of karst bank slope in the Three Gorges Project Reservoir area[J]. Hydrogeology and Engineering Geology, 47(4): 51-61. (in Chinese with English abstract) LIU C H, XU J, CAO C L, et al., 2005. Analysis of bedding-slip failure mechanism of rock slope due to hydraulic drive[J]. Chinese Journal of Rock Mechanics and Engineering, 24(19): 3529-3533. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-6915.2005.19.021 LIU K Q, LIU H Y, QI X B, 2020. Numerical study on long-term stability of soil-rock mixture slope using strength reduction technique[J]. Journal of Engineering Geology, 28(2): 327-334. (in Chinese with English abstract) LIU X R, FU Y, WANG Y X, et al., 2009. Stability of reservoir bank slope under water-rock interaction[J]. Rock and Soil Mechanics, 30(3): 613-616, 627. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2009.03.006 LUO Y F, 2015. The evaluation of long-term stability at right dam abutmet slope of Miaowei hydro power station in Lancang river[D]. Chengdu: Chengdu University of Technology. (in Chinese with English abstract) MENG W C, 2021. Effect of dry-wet cycle on expansive force and shear strength of expansive soil[J]. Railway Investigation and Surveying, 47(6): 55-60. (in Chinese with English abstract) REN Y, JIANG X Y, WU C H, et al., 2022. Experimental study on fissure properties and soil-water response of red clay slope under dry-wet cycle[J]. Water Resources and Hydropower Engineering, 53(4): 172-179. (in Chinese with English abstract) TANG L S, ZHANG P C, WANG S J, 2002a. Testing study on macroscopic mechanics effect of chemical action of water on rocks[J]. Chinese Journal of Rock Mechanics and Engineering, 21(4): 526-531. (in Chinese with English abstract) TANG L S, ZHANG P C, WANG S J, 2002b. Testing study on effects of chemical action of aqueous solution on crack propagation in rock[J]. Chinese Journal of Rock Mechanics and Engineering, 21(6): 822-827. (in Chinese with English abstract) Three Gorges Reservoir Area Geological Disaster Prevention and Control Work Headquarters, 2014. Technical requirements for the geological exploration in the Three Gorges Reservoir area for geological disaster prevention and control[M]. Wuhan: China University of Geosciences Press: 0-119. (in Chinese) WANG R B, XU W Y, MENG Y D, et al., 2014. Numerical analysis of long-term stability of left bank abutment high slope at Jinping I hydropower station[J]. Chinese Journal of Rock Mechanics and Engineering, 33(S1): 3105-3113. (in Chinese with English abstract) YAN G Q, HUANG B L, WANG X, et al., 2021. Sliding-bending failure mechanism and evaluation of bedding limestone bank slope based on rock mass deterioration in Three Gorges Reservoir area[J]. Journal of Engineering Geology, 29(3): 668-679. (in Chinese with English abstract) YAN J K, HUANG J B, LI H L, et al., 2020. Study on instability mechanism of shallow landslide caused by typhoon and heavy rain[J]. Journal of Geomechanics, 26(4): 481-491. (in Chinese with English abstract) YANG H, TANG M G, XU Q, et al., 2020. Deterioration characteristic test and quality evaluation of bank slope rock mass in hydro-fluctuation belt of Three Gorges Reservoir Area[J]. Journal of Hydraulic Engineering, 51(11): 1360-1371. (in Chinese with English abstract) YIN Y P, HUANG B L, WANG W P, et al., 2016. Reservoir-induced landslides and risk control in Three Gorges Project on Yangtze River, China[J]. Journal of Rock Mechanics and Geotechnical Engineering, 8(5): 577-595. doi: 10.1016/j.jrmge.2016.08.001 ZHANG W G, GAO X CH, GU D M, et al., 2021. Influence of cyclic wetting-drying on the shear strength of limestone with a soft interlayer[J]. Rock Mechanics and Rock Engineering, 54(8): 4369-4378. doi: 10.1007/s00603-021-02502-2 ZHANG J Y, WAN L P, PAN H Y, et al., 2017. Long-term stability of bank slope considering characteristics of water-rock interaction[J]. Chinese Journal of Geotechnical Engineering, 39(10): 1851-1858. (in Chinese with English abstract) doi: 10.11779/CJGE201710013 ZHANG Z H, DU C L, YU S, et al., 2018. Stability analysis and design of control works on Jianchuandong dangerous rock mass in Wuxia Gorge, the Three Gorges Reservoir[J]. The Chinese Journal of Geological Hazard and Control, 29(2): 48-54. (in Chinese with English abstract) ZHOU J F, 2021. Study on prediction model for rock immersion time scale and deterioration under effect of acidic solution[J] Water Resources and Hydropower Engineering, 52(8): 162-171. (in Chinese with English abstract) 邓成进, 王孔伟, 袁秋霜, 等, 2015. 库水长期升降作用下库岸边坡稳定性研究[J]. 长江科学院院报, 32(4): 96-100. https://www.cnki.com.cn/Article/CJFDTOTAL-CJKB201504022.htm 邓华锋, 方景成, 李建林, 等, 2021. 水-岩和循环加卸载次序作用下砂岩动力特性损伤演化规律[J]. 岩土力学, 42(2): 343-351. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX202102006.htm 傅晏, 2010. 干湿循环水岩相互作用下岩石劣化机理研究[D]. 重庆: 重庆大学. 胡刘洋, 张鹏, 黄波林, 2022. 三峡库区消落带岩体劣化下危岩体长期变形破坏机理: 以冠木岭为例[J/OL]. 工程地质学报, 1-11. [2022-06-14]. https://kns.cnki.net/kcms/detail/detail.aspx?dbcode=CAPJ&dbname=CAPJLAST&filename=GCDZ20221009000&uniplatform=NZKPT&v=9u6_tlouPxa4lAU2YcVmGRdoK6VK6205M_F5Ctg4vW0dyQCGTaZWAUVleKzwiGou. 胡明军, 张枝华, 殷跃平, 等, 2021. 三峡库区巫峡段消落带碳酸盐岩强度弱化研究[J/OL]. 工程地质学报, [2022-06-14]. 1-14. https://kns.cnki.net/KCMS/detail/detail.aspx?dbcode=CAPJ&dbname=CAPJLAST&filename=GCDZ20210717009. 胡其志, 周辉, 肖本林, 等, 2010. 水力作用下顺层岩质边坡稳定性分析[J]. 岩土力学, 31(11): 3594-3598. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201011040.htm 黄波林, 殷跃平, 张枝华, 等, 2019. 三峡工程库区岩溶岸坡消落带岩体劣化特征研究[J]. 岩石力学与工程学报, 38(9): 1786-1796. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201909006.htm 黄波林, 殷跃平, 李滨, 等, 2020. 三峡工程库区岩溶岸坡岩体劣化及其灾变效应[J]. 水文地质工程地质, 47(4): 51-61. https://www.cnki.com.cn/Article/CJFDTOTAL-SWDG202004007.htm 刘才华, 徐健, 曹传林, 等, 2005. 岩质边坡水力驱动型顺层滑移破坏机制分析[J]. 岩石力学与工程学报, 24(19): 3529-3533. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX200519020.htm 刘康琦, 刘红岩, 祁小博, 2020. 基于强度折减法的土石混合体边坡长期稳定性研究[J]. 工程地质学报, 28(2): 327-334. https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ202002013.htm 刘新荣, 傅晏, 王永新, 等, 2009. 水-岩相互作用对库岸边坡稳定的影响研究[J]. 岩土力学, 30(3): 613-616, 627. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX200903008.htm 罗雲丰, 2015. 澜沧江苗尾水电站右岸坝肩边坡长期稳定性评价[D]. 成都: 成都理工大学. 孟伟超, 2021. 膨胀土干湿循环对膨胀力和抗剪强度的影响[J]. 铁道勘察, 47(6): 55-60. https://www.cnki.com.cn/Article/CJFDTOTAL-TLHC202106011.htm 任意, 江兴元, 吴长虹, 等, 2022. 干湿循环下红黏土斜坡裂隙性和水土响应试验研究[J]. 水利水电技术(中英文), 53(4): 172-179. https://www.cnki.com.cn/Article/CJFDTOTAL-SJWJ202204016.htm 三峡库区地质灾害防治工作指挥部, 2014. 三峡库区地质灾害防治工程地质勘查技术要求[M]. 武汉: 中国地质大学出版社: 0-119. 汤连生, 张鹏程, 王思敬, 2002a. 水-岩化学作用的岩石宏观力学效应的试验研究[J]. 岩石力学与工程学报, 21(4): 526-531. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX200204014.htm 汤连生, 张鹏程, 王思敬, 2002b. 水-岩化学作用之岩石断裂力学效应的试验研究[J]. 岩石力学与工程学报, 21(6): 822-827. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX200206014.htm 王如宾, 徐卫亚, 孟永东, 等, 2014. 锦屏一级水电站左岸坝肩高边坡长期稳定性数值分析[J]. 岩石力学与工程学报, 33(S1): 3105-3113. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2014S1072.htm 闫国强, 黄波林, 王勋, 等, 2021. 基于岩体劣化顺层灰岩岸坡滑移-弯曲失稳机理和评价[J]. 工程地质学报, 29(3): 668-679. https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ202103010.htm 闫金凯, 黄俊宝, 李海龙, 等, 2020. 台风暴雨型浅层滑坡失稳机理研究[J]. 地质力学学报, 26(4): 481-491. doi: 10.12090/j.issn.1006-6616.2020.26.04.041 杨何, 汤明高, 许强, 等, 2020. 三峡库区消落带岸坡岩体劣化特性测试及质量评价[J]. 水利学报, 51(11): 1360-1371. https://www.cnki.com.cn/Article/CJFDTOTAL-SLXB202011006.htm 张景昱, 宛良朋, 潘洪月, 等, 2017. 考虑水-岩作用特点的典型岸坡长期稳定性分析[J]. 岩土工程学报, 39(10): 1851-1858. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201710019.htm 张枝华, 杜春兰, 余姝, 等, 2018. 三峡库区巫峡箭穿洞危岩体稳定性分析及防治工程设计[J]. 中国地质灾害与防治学报, 29(2): 48-54. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGDH201802008.htm 周济芳, 2021. 酸性溶液作用下岩石浸泡时间尺度及劣化预测模型研究[J]. 水利水电技术(中英文), 52(8): 162-171. https://www.cnki.com.cn/Article/CJFDTOTAL-SJWJ202108016.htm -
下载:
点击查看大图
计量
- 文章访问数: 355
- HTML全文浏览量: 99
- PDF下载量: 64
- 被引次数: 0
