残余强度状态下原状滑带土蠕变特性试验研究
发布时间：2018-08-25 16:20
【摘要】：三峡库区许多古滑坡在重力等内、外地质营力作用下呈现出长期而缓慢的变形特征,具有明显的蠕变属性。复活型古滑坡的滑带常处于残余强度状态,其运动特征主要受滑带土力学性质和应力状态控制,研究原状滑带土在残余强度状态下的蠕变特性,对于了解复活型古滑坡滑动机制及预测其运动趋势具有重要意义。针对三峡库区黄土坡滑坡原状滑带土开展环剪试验,研究了不同应力水平条件下滑带土在残余强度状态下的蠕变变形规律。结果表明,滑带土的蠕变速率与剪切应力比R_(CSR)(蠕变剪切应力与残余强度的比值)呈正相关变化,当R_(CSR)接近蠕变阈值1时,滑带土等速蠕变明显,部分试验条件下继而发生加速蠕变,在相同R_(CSR)条件下,土样法向应力越大,其蠕变速率也越大。采用Burger模型对蠕变过程进行模拟,获取了模型的各参数。通过分析滑带土等时蠕变曲线,获得滑带土长期抗剪强度约为0.95倍的残余强度。此外,滑带土蠕变速率受固结时间影响,蠕变速率随固结时间增加而减小,滑带土剪切强度随着固结时间和剪切位移的增加可发生一定程度的恢复。
[Abstract]:Many ancient landslides in the three Gorges reservoir area show long-term and slow deformation characteristics under the action of gravity and external geological forces and have obvious creep properties. The slip zone of the resurrected ancient landslide is usually in the state of residual strength, and its motion characteristics are mainly controlled by the mechanical properties and stress state of the sliding zone soil. The creep characteristics of the undisturbed slip zone soil under the residual strength state are studied. It is of great significance to understand the sliding mechanism and predict the movement trend of the resurrected paleo-landslide. The cyclic shear tests were carried out on the loess slope landslide in the three Gorges Reservoir area, and the creep deformation of the slip zone soil under different stress levels was studied under the condition of residual strength. The results show that the creep rate of sliding zone soil is positively correlated with the ratio of shear stress to creep shear stress to the ratio of residual strength to creep shear stress. When (CSR) is close to the creep threshold 1, the constant velocity creep of sliding zone soil is obvious. Under some experimental conditions, accelerated creep occurs. Under the same R _ (CSR) condition, the higher the normal stress of soil sample is, the higher the creep rate is. The creep process is simulated by Burger model, and the parameters of the model are obtained. By analyzing the isochronous creep curve of sliding zone soil, the long-term shear strength of sliding zone soil is about 0.95 times. In addition, the creep rate of sliding zone soil is affected by consolidation time, and the creep rate decreases with the increase of consolidation time, and the shear strength of sliding zone soil can recover to some extent with the increase of consolidation time and shear displacement.
【作者单位】： 中国地质大学教育部长江三峡库区地质灾害研究中心;中国科学院武汉岩土力学研究所;维也纳农业科技大学岩土工程研究所;武汉市测绘研究院;
【基金】：国家自然科学基金(No.41572286,No.41202199,No.41672297) 湖北省自然科学基金(No.2015CFB247) 中国博士后科学基金(No.2013M542098)~~
【分类号】：TU41
本文编号：2203448
[Abstract]:Many ancient landslides in the three Gorges reservoir area show long-term and slow deformation characteristics under the action of gravity and external geological forces and have obvious creep properties. The slip zone of the resurrected ancient landslide is usually in the state of residual strength, and its motion characteristics are mainly controlled by the mechanical properties and stress state of the sliding zone soil. The creep characteristics of the undisturbed slip zone soil under the residual strength state are studied. It is of great significance to understand the sliding mechanism and predict the movement trend of the resurrected paleo-landslide. The cyclic shear tests were carried out on the loess slope landslide in the three Gorges Reservoir area, and the creep deformation of the slip zone soil under different stress levels was studied under the condition of residual strength. The results show that the creep rate of sliding zone soil is positively correlated with the ratio of shear stress to creep shear stress to the ratio of residual strength to creep shear stress. When (CSR) is close to the creep threshold 1, the constant velocity creep of sliding zone soil is obvious. Under some experimental conditions, accelerated creep occurs. Under the same R _ (CSR) condition, the higher the normal stress of soil sample is, the higher the creep rate is. The creep process is simulated by Burger model, and the parameters of the model are obtained. By analyzing the isochronous creep curve of sliding zone soil, the long-term shear strength of sliding zone soil is about 0.95 times. In addition, the creep rate of sliding zone soil is affected by consolidation time, and the creep rate decreases with the increase of consolidation time, and the shear strength of sliding zone soil can recover to some extent with the increase of consolidation time and shear displacement.
【作者单位】： 中国地质大学教育部长江三峡库区地质灾害研究中心;中国科学院武汉岩土力学研究所;维也纳农业科技大学岩土工程研究所;武汉市测绘研究院;
【基金】：国家自然科学基金(No.41572286,No.41202199,No.41672297) 湖北省自然科学基金(No.2015CFB247) 中国博士后科学基金(No.2013M542098)~~
【分类号】：TU41
【相似文献】
相关期刊论文 前5条
1 任帮政;徐俊龙;张燕挺;徐宗恒;;滑带土及其强度影响因素研究进展[J];价值工程;2014年15期
2 徐英辉;;以礼河电厂苏家坪滑坡凝灰岩泥化土(滑带土)残余强度的试验与探讨[J];工程勘察;1985年06期
3 程东幸;刘大安;丁恩保;李学政;戴谦训;;滑带土长期强度参数的衰减特性研究[J];岩石力学与工程学报;2005年S2期
4 任光明，聂德新，，左三胜;滑带土结构强度再生研究[J];地质灾害与环境保护;1996年03期
5 ;[J];;年期
相关硕士学位论文 前2条
1 束骞;环剪试验条件下近水平岩层滑坡滑带土的力学行为特性试验研究[D];成都理工大学;2015年
2 朱峰;湘南红层滑带土直剪蠕变特性及长期强度试验研究[D];南华大学;2014年
本文编号：2203448
本文链接：https://www.wllwen.com/jianzhugongchenglunwen/2203448.html
