| 不同环剪条件下三峡库区童家坪滑坡滑带土强度特性 |
| |
| 引用本文： | 赵帆程,苗发盛,吴益平,薛阳,孟佳佳.不同环剪条件下三峡库区童家坪滑坡滑带土强度特性[J].地质科技通报,2022,41(2):315-324. |
| |
| 作者姓名： | 赵帆程 苗发盛 吴益平 薛阳 孟佳佳 |
| |
| 基金项目： | 国家自然科学基金资助项目42007267国家自然科学基金资助项目41977244国家重点研发计划项目2017YFC1501301 |
| |
| 摘 要： | 研究不同环剪条件下库岸堆积层滑坡滑带土强度特性对滑坡稳定性评价具有重要意义。针对目前在库岸堆积层滑坡滑带土力学特性方面研究薄弱的问题, 以三峡库区童家坪滑坡滑带土为研究对象, 采用ARS-E2环剪仪开展了不同剪切速率下的剪切试验, 研究了等速剪切、加速剪切以及减速剪切作用下滑带土强度变化特征。试验结果表明: 滑带土试样在恒定的低速剪切条件下更容易得到稳定的残余强度, 并且达到峰值强度后易出现"应变软化"现象; 在相同剪切应力条件下, 滑带土加速环剪和减速环剪的剪应力变化趋势基本一致, 与法向应力均呈正相关关系; 剪切速率的变化会显著影响滑带土峰值黏聚力的大小。研究成果揭示了不同环剪条件下滑带土力学特性, 可以为揭示库岸堆积层滑坡变形破坏的力学机制提供理论依据。
|
| 关 键 词： | 滑带土 环剪试验 剪切速率 峰值强度 残余强度 童家坪滑坡 三峡库区 |
| 收稿时间： | 2021-06-28 |
Strength characteristics of slip zone soils of the Tongjiaping landslide in the Three Gorges Reservoir area under different ring shear conditions |
| |
| Abstract: | Studying the strength characteristics of slip zone soils under different shear conditions is of great significance for the stability evaluation of reservoir landslides. Aiming at the weak research on the mechanical properties of landslide zone soil in the reservoir bank accumulation layer at present, in this paper, the Tongjiaping landslide slip zone soil in the Three Gorges Reservoir area is taken as an example to research the strength variation characteristics of slip zone soils under different shear test conditions. The ARS-E2 ring shear apparatus is employed to operate the shear modes of constant velocity, acceleration and deceleration on the strength variation characteristics of the slip zone soil. The experimental results indicate that the stable residual strength of slip soil samples tends to be obtained under constant low-speed shear conditions; meanwhile, the phenomenon of 'strain softening' is prone to appearing after reaching the peak strength. Moreover, the change trend of shear stress is basically the same whether accelerated ring shear or decelerated ring shear under the same shear stress condition, which both have a positive correlation with the normal stress. However, the change in shear rate will significantly affect the peak cohesion of slip zone soils. The research results reveal the mechanical properties of the sliding zone soil under different ring shear conditions, which provide a theoretical basis for revealing the mechanical mechanism of the deformation and failure of reservoir bank accumulation landslides. |
| |
| Keywords: | |
|
| 点击此处可从《地质科技通报》浏览原始摘要信息 |
| 点击此处可从《地质科技通报》下载免费的PDF全文 |
|
