土坡前端推力对降雨入渗响应的试验研究

发布时间：2018-06-06 12:24

本文选题：前端推力 + 非饱和残积土坡　；参考：《岩土力学》2017年12期

【摘要】：降雨入渗可引起坡体前端推力发生显著改变,影响土坡的稳定和安全。利用构建好的降雨模拟和监测系统,对降雨诱发非饱和残积土坡失稳过程进行全方位、多参量的实时监测,着重分析不同位置、坡度、密实度和不同降雨条件下坡体前端推力的时变规律。结果表明:边坡上部土体含水率、吸力、坡体变形和下滑推力变化幅度较大,速度较快,而下部土体变化幅度较小,速度较慢;坡体前端推力变化可分为缓慢增加、加速上升和雨后衰减3个阶段,降雨过程中陡坡和高密实度边坡反映较为强烈,下滑推力峰值大于缓坡和低密实度边坡;降雨作用下新边坡坡体应力状态变化明显,较易失稳,而老边坡则相对比较稳定;高密实度和陡坡坡体内部的高应力区域在二次或多次降雨后可完全释放,边坡具有高水平的雨后剩余下滑力和更显著的土体软化效应。研究成果对进一步揭示闽东南地区降雨入渗对非饱和土坡的影响机制及对非饱和土强度与稳定性的弱化作用具有重要的理论及实际意义。
[Abstract]:Rainfall infiltration can significantly change the front thrust of slope body and affect the stability and safety of soil slope. Based on the established rainfall simulation and monitoring system, the instability process of unsaturated residual soil slope induced by rainfall is monitored in all directions and in real time, with emphasis on the analysis of different positions and slopes. The time-varying law of the front thrust of slope body under different rainfall conditions and compactness. The results show that the variation of soil moisture content, suction, deformation and sliding thrust of the upper slope is larger and the velocity is faster, while the change of the lower soil is smaller, and the change of the thrust at the front end of the slope can be divided into slow increase. In the three stages of accelerated rise and post-rain attenuation, the steep slope and high compactness slope are strongly reflected in the rainfall process, the peak value of sliding thrust is greater than that of gentle slope and low compactness slope, and the stress state of the slope in the new edge slope changes obviously under the action of rainfall, and the slope is vulnerable to instability. But the old slope is relatively stable, the high density and the high stress area within the steep slope body can be completely released after two or more rainfall, the slope has a high level of residual sliding force after rain and a more significant softening effect of soil. The research results have important theoretical and practical significance for further revealing the influence mechanism of rainfall infiltration on unsaturated soil slope and weakening the strength and stability of unsaturated soil.
【作者单位】：福建农林大学交通与土木工程学院;福州大学岩土工程与工程地质研究所;福建省地质灾害重点实验室;
【基金】：国家自然科学基金(No.41702288) 福建省教育厅中青年教师教育科研项目(No.JAT170173) 福建省自然科学基金(No.2015J0116) 交通土建师资队伍博士化国际化工程(No.113-612014051)~~
【分类号】：TU43

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