摘要
为揭示延安丘陵区黄土雨滴溅蚀特征及其演变过程,选取晚更新世原状黄土为研究对象,利用自制的雨径、雨强可控的单雨滴模拟试验装置,对边坡浅表层采集的原状黄土进行雨滴击溅侵蚀试验,研究降雨强度和降雨历时对原状黄土侵蚀特征的影响规律。结果表明:①雨滴连续击打作用下,原状黄土表面逐渐形成一近似圆形的溅蚀坑,溅蚀坑由浅变深、由小变大,侵蚀深度随降雨历时的发展过程可描述为快速增长阶段(0~10 min)、缓慢增长阶段(10~40 min)和稳定发展阶段(40~60 min)。②侵蚀深度、侵蚀破坏直径及侵蚀扩散直径随降雨历时发展过程符合幂函数型增长,0~10 min为侵蚀变形主要增长阶段,降雨强度越大,土壤侵蚀作用越显著,0~10 min阶段的侵蚀深度占总侵蚀深度比例可达81%以上;降雨历时约10 min后,溅蚀面上横向侵蚀范围基本趋于稳定状态,侵蚀深度、侵蚀破坏直径及侵蚀扩散直径均随降雨强度呈正相关,且侵蚀扩散直径D约为侵蚀破坏直径D 0的2.71~3.55倍。③强降雨是诱发黄土边坡发生侵蚀灾害和水土流失的重要影响因素,建议采用坡面植绿、加筋和防排水等防护措施,增强坡面抗侵蚀能力,降低黄土边坡浅层水蚀灾害发生。研究成果可为黄土地区降雨侵蚀灾害防治提供参考。
In order to reveal the raindrop splash erosion characteristics and evolution process of loess in Yan an hilly region,the authors selected the soil of Late Pleistocene as the research object,and used self-made raindrop simulation test device with controllable rain diameter and rain intensity to conduct the raindrop splash erosion test on the raw loess collected from the shallow surface of the slope and investigate the influence law of rainfall intensity and rainfall duration on the erosion characteristics of loess.The results show that an approximately circular spattering pit is gradually formed on the surface of undisturbed loess under the continuous impact of raindrops,and the pattering pit changes from shallow to deep and from small to large.The development process of erosion depth with different rainfall duration can be described as rapid growth stage(0-10 min),slow growth stage(10-40 min)and stable development stage(40-60 min).The development of erosion depth,erosion damage diameter and erosion diffusion diameter with different rainfall duration showed a power function growth trend,and 0-10 min is the main growth stage of erosion deformation.The greater the rainfall intensity is,the more significant the soil erosion is.The erosion depth of 0-10 min accounted for more than 81%of the total erosion depth,and the lateral erosion range on the splash surface is stabilized gradually after the rainfall lasted for about 10 minutes.The erosion depth,erosion damage diameter and erosion diffusion diameter are positively correlated with rainfall intensity,and the erosion diffusion diameter D is about 2.71-3.55 times the erosion damage diameter D 0.The heavy rainfall is an important factor that induces erosion disasters and water and soil erosion on loess slope,so the it is recommended to take protective measures to enhance the slope anti-erosion ability,including green planting,reinforcement and waterproof and drainage,which can reduce the occurrence of shallow water erosion disaster on loess slope.This research can provi
作者
赵霞玉
邱明明
周占江
赵艳秋
郭富杭
ZHAO Xiayu;QIU Mingming;ZHOU Zhanjiang;ZHAO Yanqiu;GUO Fuhang(School of Architectural Engineering,Yan an University,Shanxi Yan an 716000,China)
出处
《中国地质调查》
CAS
2023年第2期111-117,共7页
Geological Survey of China
基金
陕西省科技厅“黄土沟壑区新建重大工程场地地质与生态环境监测评估关键技术研究与示范(编号:2020ZDLSF06-03)”
延安市科技局“黄土沟壑区边坡降雨入渗致灾模式及生态防护技术研究(编号:2019ZCSY-006)”
延安大学科研计划项目“降雨入渗下高填方结构性黄土边坡稳定性演化机理研究(编号:YDY2020-36)”
国家级大学生创新创业训练计划项目“降雨水力侵蚀作用对原状黄土变形破坏规律的影响(编号:202110719009)”联合资助。
关键词
黄土边坡
降雨强度
原状黄土
雨滴溅蚀
溅蚀过程
loess slope
rainfall intensity
undisturbed loess
raindrop splash erosion
splash erosion process
