人工模拟降雨条件下坡面侵蚀特性的模型试验研究  

Model Test Study on Slope Erosion Characteristics under Artificial Simulated Rainfall Conditions

作　　者：孙狂飙 袁超[2,3] 周峙 罗易 米敏[2,3] 张家铭 SUN Kuangbiao;YUAN Chao;ZHOU Zhi;LUO Yi;MI Min;ZHANG Jiaming(Anhui Transportation Holdings Group Co.,Ltd.,Hefei 230088,China;Academic Research Center of Engineering Geology and Geotechnical Protection,MOE Engineering Research Center of Rock-Soil Drilling & Excavation and Protection,China University of Geosciences (Wuhan), Wuhan 430074, China;Faculty of Engineering , China University of Geosciences (Wuhan),Wuhan 430074 ,CAzna)

机构地区：[1]安徽省交通控股集团有限公司,安徽合肥230088 [2]中国地质大学(武汉)工程地质与岩土防护学术创新基地&岩土钻掘与防护教育部工程研究中心,湖北武汉430074 [3]中国地质大学(武汉)工程学院,湖北武汉430074

出　　处：《安全与环境工程》2019年第3期62-69,共8页Safety and Environmental Engineering

基　　金：安徽省2018年度交通运输科技进步计划项目(2018030);中国地质大学(武汉)中央高校基本科研业务费专项资金项目(1810491A24);安徽省交通控股集团交通科技攻关项目(KKJ-2017-20);岩土钻掘与防护教育部工程研究中心开放基金项目(201803)

摘　　要：工程斜坡体水土流失主要由水力侵蚀的导致,为研究土壤侵蚀的水动力过程,通过足尺模型试验,人工模拟降雨条件下不同降雨强度和坡度对坡面侵蚀特征的影响。试验结果表明,坡度由15°增大至53°、降雨强度由50 mm/h上升至100 mm/h时:①坡面初始产流时间减小,径流强度曲线以指数型增长,坡度与径流强度成负相关,这是由于雨滴打击作用致使降雨初期径流强度缓慢增长,后快速增大至峰值;②由于径流作用,径流含沙量前阶段出现短时间减小,随后恢复增大趋势,且降雨强度和坡度增幅越明显,径流含沙量越大,两者交互作用大于单指标对径流含沙量的影响程度,这是由于雨滴击溅作用加强了水流对泥沙的迁移能力,进而增大了径流含沙量,且产沙量与径流量的关系密切,径流强度直接影响产沙量的大小,两者的增长趋势成正相关;③坡面侵蚀最先产生细沟,细沟侵蚀导致产沙量快速增加,随着降雨历时的推移,侵蚀类型最终发展为浅沟、切沟,并成为侵蚀产沙的主要方式,这是由于雨滴打击作用促进了侵蚀沟的发育,增强了径流对颗粒的分选能力,从而增加了细粒土的流失。The soil erosion of engineering slope is mainly caused by hydraulic erosion. In order to study the hydrodynamic process of soil erosion, this paper simulates the influence of different rainfall intensity and gradient on the slope erosion characteristics under rainfall conditions through model test. The test results show that when the slope increases from 15° to 53°,and the rainfall intensity increases from 50mm/h to 100mm/h,①the initial slope runoff time decreases, the runoff intensity shows exponential growth, and slope is negatively related to the intensity of runoff. The impact of raindrop makes the intensity of runoff increase slowly at the beginning of rainfall and then increases rapidly to the peak;②due to the runoff effect, the sediment concentration in the pre-stage decreases for a short time and then recovers the trend of increase. In addition, the more obvious the increase of rainfall intensity and gradient, the greater the sediment concentration in runoff, and the interaction between the two is greater than that of single index. Because of the impact of raindrop splash, the ability of water flow to sediment transport is strengthened, and thus the sediment content of runoff is increased.Sediment yield is closely related to runoff,and runoff intensity directly affects sediment yield;③the slope erosion first produces rills,and rill erosion leads to rapid increase of sediment yield With the passage of rainfall, erosion type eventually develops into shallow gullies and gullies, and becomes the main method of erosion and sediment production. Raindrop impact promotes the development of erosion gully, enhances the ability of runoff to separate particles, and increases the loss of fine soil.

关 键 词：工程斜坡 人工模拟降雨 降雨强度 坡度 产沙量 坡面侵蚀特征 模型试验 

分 类 号：X43[环境科学与工程—灾害防治] P642.22[天文地球—工程地质学]