降雨条件下边坡渐进性破坏的模型试验研究

Model experimental study of asymptotic failure of slopes under rainfall conditions

摘要

黄土滑坡因气候变化、人为干扰及工程活动加剧而频繁发生，而降雨入渗是主要原因之一。需要研究降雨诱发黄土滑坡的变形演化机理，并探讨施加防护措施对边坡稳定性的影响。选取陕西省黄延高速公路K615公里处阳坡窑黄土边坡为研究对象，通过设计两组物理模型试验，结合分布式光纤传感测量技术和人工降雨模拟系统，全面监测边坡在降雨过程中的变形、含水率、孔隙水压力和土压力等参数变化。结果表明：降雨入渗过程中，黄土边坡的含水率增加导致土体强度降低，孔隙水压力升高，最终引发边坡失稳破坏的演化机制。第二组试验通过埋设木板防护措施，显著延缓了边坡破坏过程，表明防护措施对增强边坡稳定性具有积极作用。分布式光纤能够准确的检测边坡内部随降雨时间的变形，为降雨诱发黄土滑坡的灾害预警和防治提供了重要依据，也为光纤传感技术在边坡监测中的应用提供了新的思路和方法。

Abstract

Loess landslides occur frequently due to climate change, anthropogenic disturbances and intensified engineering activities, and rainfall infiltration is one of the main causes. There is a need to study the deformation evolution mechanism of rainfall-induced loess landslides and to explore the influence of applied protective measures on slope stability. The loess slope at K615 km of Huangyan Expressway in Shaanxi Province, Yangpoyao slope, was selected as the research object, and the deformation, water content, pore water pressure, and soil pressure of the slope during rainfall were comprehensively monitored by designing two sets of physical model tests and combining with distributed optical fibre sensing and measurement technology. The result show that during rainfall infiltration, the increase in water content of loess slopes leads to a decrease in soil strength and an increase in pore water pressure, which ultimately triggers the evolutionary mechanism of slope destabilisation and damage. The second group of tests significantly slowed down the slope destruction process by burying plank protection measures, indicating that the protection measures have a positive effect on enhancing the stability of slopes. The research result provide an important basis for the disaster warning and prevention of rainfall-induced loess landslides, and also provide new ideas and method for the application of fibre-optic sensing technology in slope monitoring.

关键词

模型试验 / 黄土边坡 / 分布式光纤 / 破坏机理

Key words

model test / loess slope / distributed fibre optics / failure mechanism

Author summay

周亮梅(1999—), 女, 硕士研究生, 主要从事岩土工程相关研究。E-mail: [e-mail]

基金资助

国家自然科学基金项目(52279118)

国家自然科学基金青年基金项目(52009129)