基于现场原型试验的斜坡降雨入渗分析及入渗模型研究  

Rainfall infiltration analysis and infiltration model of slope based on in-situ tests

作　　者：郭智辉 简文彬[1,2] 刘青灵[3] 聂闻 GUO Zhi-hui;JIAN Wen-bin;LIU Qing-ling;NIE Wen(Department of Geotechnical and Geological Engineering,Fuzhou University,Fuzhou,Fujian 350108,China;Engineering Research Center of Geological Engineering,Fuzhou University,Fuzhou,Fujian 350108,China;College of Zijin Mining,Fuzhou University,Fuzhou,Fujian 350108,China;Quanzhou Institute of Equipment Manufacturing,Haixi Institutes,Chinese Academy of Sciences,Quanzhou,Fujian 362200,China)

机构地区：[1]福州大学岩土与地质工程系,福建福州350108 [2]福州大学地质工程福建省高校工程研究中心,福建福州350108 [3]福州大学紫金矿业学院,福建福州350108 [4]中国科学院海西研究院泉州装备制造研究所,福建泉州362200

出　　处：《岩土力学》2021年第6期1635-1647,共13页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.41861134011)。

摘　　要：我国东南沿海地区台风暴雨多发,而台风暴雨条件下雨水的入渗是东南丘陵山地滑坡的一个重要诱因。有必要深入研究不同地质地形斜坡环境条件下雨水入渗湿润锋的迁移规律。通过滑坡原位监测试验场的监测数据,分析了降雨入渗时空变化规律,建立了综合考虑土体初始含水率分布不均匀性和斜坡环境的降雨入渗模型,并利用现场试验结果及前人经典模型计算结果对该模型进行了对比分析。结果表明:(1)降雨入渗初期,不同深度含水率增长斜率较陡,随着时间的推移,斜率逐渐减缓。当累计降雨量达到44.4mm以上时,含水率剖面图由Z型变为反S型,随着降雨量的减少,雨水入渗过程由积水入渗转变为非积水入渗。入渗后期,不同深度含水率增长率趋于一个常数,而达到稳定入渗阶段。(2)湿润锋迁移速度随降雨量增大而增加,降雨初期,雨水入渗率大,湿润锋迁移速率快,且迁移速度随土层埋深的增大而减少。(3)改进的降雨入渗模型计算的湿润锋深度随时间的变化结果与现场监测试验结果较为吻合,考虑斜坡倾角和初始含水率分布的不均匀性可提高Green-Ampt模型计算精度。该研究结果对于建立有效的台风暴雨型滑坡的预警模型具有一定的指导意义。Typhoon rainstorms occur frequently in the southeastern coastal areas of China. The infiltration of rainwater under typhoon rainstorm conditions is an important cause of landslides in hilly mountains. Therefore, it is of great significance to study the migration law of rainwater infiltration wetting front under different geological environmental conditions. The temporal and spatial changes of rainfall infiltration were analyzed based on the monitoring data collected by the in-situ test of a landslide. A comprehensive rainfall infiltration model was established, which takes into account the nonuniform distribution of the initial water content of the soil and the slope environment. Then this model was verified by comparing to field test results and the predictions from existing classic models. The results demonstrate that: 1) At the initial stage of rainfall infiltration, the increasing slope of water content at different depths was steep. With the increase of time, the slope gradually slowed down. When the accumulated amount of rainfall reached 44.4 mm or more, the shape of the water profile changed from "Z" to reverse "S". As the rainfall intensity decreased, the type of rainwater infiltration process changed from water infiltration to non-water infiltration. At the later stage of infiltration, the growth rate of water content at different depths tended to be constant, and a stable infiltration stage was reached. 2) The migration speed of the wetting front increased with increasing rainfall. At the beginning of the rainfall, the rainwater infiltration rate was large. The migration speed of the wetting front was fast, and it decreased with the increase of soil depth. 3) The results of wetting front depth change over time calculated based on the improved rainfall infiltration model are consistent with the field monitoring test results, indicating that taking into account the slope angle and the inhomogeneity of the initial water content distribution can improve the accuracy of the predictions of the Green-Ampt mode

关 键 词：原型监测 体积含水率 湿润锋 GREEN-AMPT入渗模型 

分 类 号：TU413[建筑科学—岩土工程]