岩土力学 ›› 2021, Vol. 42 ›› Issue (3): 863-873.doi: 10.16285/j.rsm.2020.0660

• 岩土工程研究 • 上一篇    下一篇

含砾滑带土复活启动强度研究

任三绍1, 2, 3,张永双1, 3,徐能雄2,吴瑞安4,刘筱怡4   

  1. 1. 中国地质科学院水文地质环境地质研究所,河北 石家庄 050061;2. 中国地质大学(北京) 工程技术学院,北京 100083; 3. 中国地质调查局第四纪年代学与水文环境演变重点实验室,河北 石家庄 050061;4. 中国地质科学院地质力学研究所,北京 100081
  • 收稿日期:2020-05-20 修回日期:2020-12-30 出版日期:2021-03-11 发布日期:2021-03-17
  • 通讯作者: 张永双,男,1968年生,博士,研究员,主要从事工程地质与地质灾害研究。E-mail: zhys100@sohu.com E-mail:rensanshao123@163.com
  • 作者简介:任三绍,男,1991年生,博士研究生,主要从事工程地质与地质灾害研究
  • 基金资助:
    国家自然科学基金重点项目(No.41731287);国家自然科学基金重大专项项目(No.41941017)。

Mobilized strength of sliding zone soils with gravels in reactivated landslides

REN San-shao1, 2, 3, ZHANG Yong-shuang1, 3, XU Neng-xiong2, WU Rui-an4, LIU Xiao-yi4   

  1. 1. Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, Hebei 050061, China; 2. School of Engineering and Technology, China University of Geosciences, Beijing 100083, China; 3. Key Laboratory of Quaternary Chronology and Hydrological Environmental Evolution, China Geological Survey, Shijiazhuang, Hebei 050061, China; 4. Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China
  • Received:2020-05-20 Revised:2020-12-30 Online:2021-03-11 Published:2021-03-17
  • Supported by:
    This work was supported by the Key Project of National Natural Science Foundation of China(41731287) and the Major Special Projects of National Natural Science Foundation of China(41941017).

摘要: 砾石在古滑坡滑带土中广泛存在,确定含砾滑带土的启动强度是古滑坡稳定性评价和灾害防范的关键。以2018年甘肃舟曲县江顶崖古滑坡复活事件为例,基于试验测试和反演分析方法,研究了含砾滑带土的复活启动强度。结果表明: (1)长距离剪切后,滑带土中的胶结作用已逐渐丧失,其残余抗剪强度主要由土颗粒之间的滑动摩擦阻力和咬合作用所导致,砾石含量较高时土颗粒之间的力较强,因而其残余强度也相对较大。剪切面摩擦系数与粗糙度呈正线性相关性,砾石改变了剪切面的粗糙度,使剪切面摩擦阻力增大,导致其残余强度增大。(2)含砾滑带土的残余内摩擦角同时受黏粒含量和砾石含量的控制,与黏土质滑带土主要受黏粒含量控制的机制具有明显差异,建议采用砾石含量与黏粒含量之比作为估算含砾滑带土残余内摩擦角的指标。(3)古滑坡复活启动强度一般大于残余强度但略小于恢复强度,复活启动前的滑带土强度已经由恢复强度向残余强度逐渐衰减,此时古滑坡整体上处于蠕滑状态,在外力作用下,滑带土强度易发生急剧衰减,从而诱发古滑坡加速滑动。

关键词: 滑坡复活, 含砾滑带土, 残余强度, 强度恢复, 启动强度

Abstract: Gravels are widely found in the sliding zone soils (SZS) of ancient landslides. It is the key to determine the mobilized strength of SZS with gravels for the stability evaluation and prevention of ancient landslides. Taking the reactivation of Jiangdingya ancient landslide in Zhouqu County, Gansu Province in 2018 as an example, the mobilized strength of SZS with gravels was studied based on the test and back analysis. The results suggested that: (1) after long-distance shearing, the cementation in the SZS has been gradually lost, and the residual strength is mainly controlled by the sliding frictional resistance and occlusion between the soil particles. When the gravel content is higher, the interaction force between the soil particles is stronger, so the residual strength is relatively larger. There is a positive linear correlation between the friction coefficient and roughness of the shear surface. The gravel changes the roughness of the shear surface, which increases the friction resistance and leads to the increase of its residual strength. (2) The statistical analysis showed that the φr of SZS with gravels is controlled by both clay and gravel content, which is significantly different from the mechanism that the φr of SZS without gravels is mainly controlled by clay content. It is suggested that the ratio of gravel content to clay content should be used as an index to estimate the φr of SZS with gravels. (3) The mobilized strength of ancient landslides is generally greater than the residual strength, but slightly less than the recovery strength. Before reactivation, the strength of SZS has gradually attenuated from the recovery strength to the residual strength. At this time, the ancient landslide is in the creeping state as a whole. Under the action of external forces, the strength of SZS tends to decay sharply, which induces the accelerated sliding of the ancient landslide.

Key words: landslide reactivation, sliding zone soils with gravels, residual strength, strength recovery, mobilized strength

中图分类号: TU457
[1] 黄德昕, 温韬, 陈宁生, . 考虑能量演化的岩石残余强度确定方法[J]. 岩土力学, 2025, 46(9): 2825-2836.
[2] 汪明元, 孙吉主, 王勇, 杨洋, . 基于CPTu的状态相关边界面模型标定研究[J]. 岩土力学, 2023, 44(11): 3280-3287.
[3] 闫琦玮, 李新坡, 何思明, 罗渝, 田宏岭, 吴永, . 典型红层滑坡滑带土自愈合效应试验研究[J]. 岩土力学, 2020, 41(9): 3041-3048.
[4] 陈润发, 缪林昌, 孙潇昊, 吴林玉, 王呈呈. 添加氧化铝对微生物修复裂缝影响的分析[J]. 岩土力学, 2020, 41(3): 933-938.
[5] 谢辉辉, 许振浩, 刘清秉, 胡桂阳, . 干湿循环路径下弱膨胀土峰值及残余强度演化研究[J]. 岩土力学, 2019, 40(S1): 245-252.
[6] 邵生俊, 陈 菲, 邓国华, . 基于平面应变统一强度公式的结构性黄土填料 挡墙地震被动土压力研究[J]. 岩土力学, 2019, 40(4): 1255-1262.
[7] 江强强, 刘路路, 焦玉勇, 王 浩, . 干湿循环下滑带土强度特性与微观结构试验研究[J]. 岩土力学, 2019, 40(3): 1005-1012.
[8] 黄宏翔,陈育民,王建平,刘汉龙,周晓智,霍正格, . 钙质砂抗剪强度特性的环剪试验[J]. , 2018, 39(6): 2082-2088.
[9] 李 磊,蒋明镜,张伏光, . 深部岩石考虑残余强度时三轴试验离散元定量模拟及参数分析[J]. , 2018, 39(3): 1082-1090.
[10] 林 波,张 锋,冯德成,马宏岩,冯 鑫,. 冻融循环作用后饱和黏土的应变速率效应试验研究[J]. , 2017, 38(7): 2007-2014.
[11] 李海潮,张 升,. 基于修正Lemaitre应变等价性假设的岩石损伤模型[J]. , 2017, 38(5): 1321-1326.
[12] 刘清秉,王 顺,夏冬生,项 伟,苏爱军,王菁莪,刘 晓,. 残余强度状态下原状滑带土蠕变特性试验研究[J]. , 2017, 38(5): 1305-1313.
[13] 马 林. 钙质土的剪切特性试验研究[J]. , 2016, 37(S1): 309-316.
[14] 缪海波,殷坤龙,王功辉,. 库岸深层老滑坡间歇性复活的动力学机制研究[J]. , 2016, 37(9): 2645-2653.
[15] 蒋秀姿,文宝萍. 缓慢复活型滑坡滑带土的蠕变性质与特征强度试验研究[J]. , 2015, 36(2): 495-501.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
No Suggested Reading articles found!