降雨特性对延安山区边坡黄土溅蚀特征的影响  

Effects of Rainfall Characteristics on Splash Erosionof Loess on Slope in Yan'an Mountain Region

作　　者：邱明明 周占江 郭富杭 赵艳秋 赵霞玉 QIU Mingming;ZHOU Zhanjiang;GUO Fuhang;ZHAO Yanqiu;ZHAO Xiayu(School of Architectural Engineering,Yan'an University,Yan'an 716000,China)

机构地区：[1]延安大学建筑工程学院,陕西延安716000

出　　处：《甘肃科学学报》2023年第5期84-89,共6页Journal of Gansu Sciences

基　　金：国家级大学生创新创业训练计划项目(202110719009);陕西省重点研发计划资助项目(2020ZDLSF06-03);陕西省教育厅服务地方专项计划项目(21JC035);延安大学科研计划资助项目(CXY202006,YDY2020-36)。

摘　　要：降雨作用下黄土高原区边坡土体溅蚀灾害问题突出。以延安山区边坡原状黄土为研究对象,通过自制降雨特性可控的单雨滴模拟试验装置,进行不同降雨强度q(10滴/min、25滴/min、50滴/min、100滴/min、150滴/min)、雨滴直径d(3 mm、4 mm、5 mm)、雨滴落高h(1 000 mm、1 500 mm、2 000 mm)条件下原状黄土击溅侵蚀试验,研究降雨特性对延安山区边坡黄土溅蚀特征的影响规律。研究结果表明,原状黄土在雨滴持续击打作用下逐渐形成由小变大、由浅变深的圆形溅蚀坑,溅蚀深度与降雨历时的关系符合幂函数发展趋势,其发展过程可分为3个阶段,即快速增长阶段(0~10 min)、缓慢增长阶段(10~40 min)和稳定发展阶段(40~60 min);溅蚀深度与降雨强度之间近似呈线性增长关系;雨滴直径和落高对溅蚀深度影响显著,且溅蚀深度与雨滴直径和雨滴落高之间均呈正相关关系;横向溅蚀范围与降雨强度、雨滴直径和雨滴落高之间均呈单调递增趋势,溅蚀扩散直径D为溅蚀破坏直径D_0的2.2~3.6倍。研究结果可为黄土高原地区边坡土壤击溅侵蚀防治提供科学依据。Splash erosion of slope soil in Loess Plateau under rainfall is a serious problem.In this paper,the undisturbed loess slope in Yan'an mountain region is taken as the research object.Through the self-made single raindrop simulation test device with controllable rainfall characteristics,the splash erosion tests of undisturbed loess were carried out under different rainfall intensity q(10 drops/min,25 drops/min,50 drops/min,100 drops/min,150 drops/min),raindrop diameter d(3.0 mm,4.0 mm,5.0 mm)and raindrop height h(1000 mm,1500 mm,2000 mm)to study the influence of rainfall characteristics on the splash erosion characteristics of loess slope in Yan'an mountain region.The results show that the circular erosion pits gradually form from small to large and from shallow to deep under the continuous impact of raindrops.The relationship between the erosion depth and rainfall duration is in line with the power function development trend,and the development process can be divided into three phases:rapid growth phase(0~10 min),slow growth phase(10~40 min)and stable development phase(40~60 min).The relationship between splash depth and rainfall intensity increases linearly.The effect of drop diameter and drop height on the splash depth is significant,and the splash depth is positively correlated with the drop diameter and drop height.The range of splash erosion increases monotonically with rainfall intensity,raindrop diameter and raindrop height,and the splash erosion diffusion diameter D is about 2.2~3.6 times of the splash erosion damage diameter D 0.The research results could provide a scientific basis for the prevention and control of soil splash erosion in the Loess Plateau.

关 键 词：黄土边坡 模拟降雨 原状黄土 溅蚀过程 演变规律 

分 类 号：TU411[建筑科学—岩土工程] S157[建筑科学—土工工程]