不同降雨条件下土质开挖坡面的细沟间侵蚀特征  

Characteristics of Rill Erosion on Soil Excavation Slope under Different Rainfall Conditions

作　　者：李熙 王重卿 车艳红 陈垚 LI Xi;WANG Chongqing;CHE Yanhong;CHEN Yao(Research Center of Electric Power Plant,Fujian Electric Power Research Institute of State Grid,Fuzhou 350007,China)

机构地区：[1]国网福建省电力有限公司电力科学研究院电源技术研究中心,福州350007

出　　处：《亚热带资源与环境学报》2023年第2期78-85,共8页Journal of Subtropical Resources and Environment

基　　金：国网福建省电力有限公司科技项目(521304200006)。

摘　　要：土质开挖坡面的细沟间侵蚀受降雨影响较大,因此,为了更加科学地治理土质开挖坡面水土流失问题,本研究开展野外人工模拟降雨试验,设计了0.60、1.10、1.61、2.12、2.54 mm·min^(-1)这5个不同雨强以及10°、15°、20°等3个坡度的原位试验,研究其在不同降雨条件下的侵蚀特性。结果表明:(1)土质开挖坡面以地表径流为主要的水文过程,地表径流量占总降雨量的67.2%~85.4%;(2)径流流速和雷诺数与雨强和坡度-雨强的交互作用(I×S)呈极显著相关(P<0.01),曼宁系数、阻力系数和水流功率与雨强均不相关,弗劳德数与雨强、坡度及其交互作用均不相关,各坡度开挖坡面雷诺数为48.98~392.92,阻力系数与雷诺数之间不存在明显关系,土质开挖坡面存在“增阻”现象;(3)采用3种常用的细沟间侵蚀模型计算土质开挖坡面土壤剥蚀率,数据拟合效果表明,模型1>模型3>模型2,且凸曲线型坡度因子指标更适用于土质开挖坡面土壤剥蚀率的计算。根据WEPP细沟间侵蚀方程(模型1)计算得到土质开挖坡面土壤可蚀性因子为0.332×10^(6) kg·s·m^(-4)。研究成果可为建立土质开挖坡面水土流失量预测模型提供数据基础。The rill erosion on the soil excavation slope is greatly affected by rainfall.Therefore,in order to control the soil and water loss on the soil excavation slope more scientifically,the field artificial simulated rainfall test is adopted in this study.Five in-situ tests with different rainfall intensities of 0.60,1.10,1.61,2.12 and 2.54 mm·min^(-1) and three slopes of 10°,15°and 20°are designed to explore the erosion characteristics under different rainfall conditions.The results show that,1)surface runoff of soil excavation slope is one of the main hydrological process,and the surface runoff accounts for 67.2%~85.4%of the total rainfall.2)There is a very significant positive correlation between runoff velocity and Reynolds number and rainfall intensity and the interaction of rainfall intensity and slope-rainfall intensity(I×S).(P<0.01).Manning coefficient,resistance coefficient and flow power are not correlated with rain intensity.Froude number is not correlated with rain intensity,slope and its interaction.The Reynolds number of excavation slope of each slope is 48.98~392.92.There is no obvious relationship between resistance coefficient and Reynolds number.There is“increasing resistance”phenomenon on soil excavation slope.3)Three commonly used rill erosion models are used to calculate the soil erosion rate of soil excavation slope.The data fitting effect shows that model 1>model 3>model 2,and the convex curve slope factor index is more suitable for the calculation of soil erosion rate of soil excavation slope.Interrill erodibility adopted in the WEPP model was determined as 0.332×10^(6) kg·s·m^(-4).The results provide valuable data for establishing water erosion prediction model of engineering excavated slope.

关 键 词：土质开挖面 人工模拟降雨 水动力学 细沟间侵蚀 

分 类 号：K903[历史地理—人文地理学]