水土保持研究2024，Vol.31Issue(3)：143-152,159,11.DOI:10.13869/j.cnki.rswc.2024.03.043
红壤工程堆积体坡面径流水动力特性研究
Study on the Dynamic Hydrodynamic Characteristics of Runoff on the Slope of Red Soil Engineering Accumulation
摘要
Abstract
[Objective]The aim of this study are to explore the characteristics of hydrodynamic parameters on the slope runoff of two typical artificial disturbance engineering accumulations,bare slope and soil rock mixture under rainfall conditions,to quantify the critical conditions for erosion dynamics of accumulations,and to lie the foundation for elucidating the erosion dynamics mechanism of accumulations.[Methods]This study focused on the loose red soil engineering accumulation as the research object.The runoff dynamic hydrodynamic characteristics of bare slope and mixed soil and rock accumulation(20％gravel content)under different rainfall intensity conditions through simulated rainfall experiments were analyzed.The critical dynamic conditions for erosion of different accumulations were quantified.The research on the internal mech-anisms of accumulation erosion was conducted.[Results]The runoff of accumulations changed from laminar slow flow to laminar jet flow,and Darcy-Weisbach increased by 1.40～3.54 times,with the increase of rainfall intensity from 1.0 mm/min to 2.0 mm/min.The runoff shear stress and runoff power of the accumu-lation showed an overall increasing trend with the increase of rainfall intensity.When the rainfall intensity was 1.0 mm/min,the average runoff shear stress of the soil rock mixed accumulation decreased by 44.99％compared to the bare slope.However,when the rainfall intensity was more than 1.5 mm/min,it increased by 2.90％～18.50％.The gravel action reduced the average runoff power by 10.38％～68.13％compared to bare slopes under three rainfall intensities.The gravel action also reduced the unit runoff power and the unit energy of the water flow section by 20.11％～40.45％and 21.06％～37.57％,respectively.The runoff power parameter was used to characterize the dynamic changes of slope erosion in accumulations.When the rainfall intensity was less than 1.5 mm/min,gravel could inhibit accumulation erosion,and the critical runoff power increased by 19.38％～138.12％,resulting in a decrease of 79.87％～83.51％in soil erodibility.When the rainfall intensity reached up to 2.0 mm/min,the critical runoff power decreased by 97.87％,and the soil erodibility increased by 347.43％.[Conclusion]Rainfall intensity has a significant impact on the hydrodynamic parameters of both bare slopes and mixed soil and rock accumulations.However,as rainfall intensity increases,the role of gravel in regulating erosion of the accumulations will change,a critical rainfall intensity can be indentified.关键词
水土保持/红壤堆积体/降雨/水动力参数/侵蚀Key words
soil and water conservation/red soil accumulation/rainfall test/dynamic hydrodynamic/erosion分类
农业科技引用本文复制引用
芮茂刚,周彦辰..红壤工程堆积体坡面径流水动力特性研究[J].水土保持研究,2024,31(3):143-152,159,11.基金项目
云南省水利厅科技计划项目"红壤土壤侵蚀规律研究"(YNSL2022-06) （YNSL2022-06）
