工程堆积体土石质边坡径流特征及其产沙效应  

Runoff characteristics of earth-rock slope of engineering deposit and its sediment yielding effect

作　　者：张孝中 袁瀛 王文龙 ZHANG Xiaozhong;YUAN Ying;WANG Wenlong(Shaanxi Provincial Planning and Research Institute of Soil and Water Conservation,Xi an 710004,Shaanxi,China;State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest A&F University,Yangling 702100,Shaanxi,China;Institute of Water and Soil Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,Shaanxi,China)

机构地区：[1]陕西省水土保持勘测规划研究所,陕西西安710004 [2]西北农林科技大学水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [3]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《水利水电技术》2018年第9期133-141,共9页Water Resources and Hydropower Engineering

基　　金：国家自然科学基金项目(40771127);水利部公益性行业专项(201201048;201201047);中国科学院西部行动计划项目(KZCX2-XB3-13)

摘　　要：工程堆积体边坡侵蚀产沙是生产建设项目区新增水土流失的主要来源之一。通过室内模拟降雨试验,以土质边坡为对照,研究了不同雨强(1. 0 mm/min、2. 5 mm/min)不同砾石质量含量(10%～30%)条件下风沙区工程堆积体土石质边坡径流强度与流速特征及其对产沙的影响。结果表明:(1)各雨强下径流强度随砾石含量增大先减后增,10%砾石含量堆积体边坡径流强度较土质边坡降低3. 3%～38. 6%,20%～30%砾石含量堆积体坡面径流强度较土质坡面增加7. 7%～94. 7%。(2)含砾石边坡流速较土质边坡降低0～45. 8%。1. 0～2. 0 mm/min雨强下,流速随砾石含量增大变化趋势与径流强度一致,而在2. 5 mm/min雨强下则持续减小。(3)土质边坡流速与径流强度关系可通过幂函数描述(P <0. 01),而砾石含量越高,雨强越大时,二者之间的关系转变为开口向下的二次函数形式(P <0. 01)。(4)次降雨产沙量与径流流速、径流强度及其二者交互项呈极显著线性相关关系,其中,流速可作为预测风沙区工程堆积体土石质边坡次降雨侵蚀产沙量的最优选指标。研究结果可为工程堆积体土石质边坡侵蚀产沙预测提供一定的参考。The sediment yield from the slope erosion of engineering deposit is one of the main sources of the new additional water-soil loss within the project areas of production and construction.The intensity and flow velocity of the runoff from the earth-rock slope of engineering deposit within windy-sandy region and their influences on the sediment yield under the condition with different rainfall intensities(1.0~2.5 mm/min)and gravel contents(10%~30%)are studied herein with the comparison made with those of earth slope through the relevant indoor simulative rainfall experiment.The result shows that(1)the runoff intensities under all the rainfall intensities are decreased at first and then increased along with the increase of the gravel content;for which the runoff intensity from the slope of the deposit with the gravel content of 10%is decreased by 3.3%~38.6%when compared with that of earth slope,while the runoff intensity from the slope of the deposit with the gravel content of 20%~30%is increased by 7.7%~94.7%when compared with that of earth slope.(2)The flow velocity from the slope containing gravel is decreased by 0~45.8%when compared with that of earth slope.Under the rainfall intensity of 1.0~2.0 mm/min,the changing trend of the flow velocity is consistent with that of the runoff intensity along with the increase of the gravel content,but it is continuously decreased under the rainfall intensity of 2.5 mm/min.(3)The relationship between the flow velocity and the runoff intensity from earth slope can be described through the power function(P<0.01),while the higher the gravel content is and the larger the rainfall intensity is,the relationship between both of them is transformed into the form of an open downward quadratic function(P<0.01).(4)The secondary rainfall sediment yield exhibits a significant linear correlation with the flow velocity and intensity of runoff as well as the interaction of both of them;in which the flow velocity can be taken as the most preferable index for predicting the sediment yield from

关 键 词：流速 径流强度 工程堆积体 砾石含量 风沙土 产沙量 

分 类 号：S157.1[农业科学—土壤学]