This study aims to explore the runoff and sediment yield characteristics on loose engineering accumula-tions under different rainfall conditions.Based on field investigations,we developed models of accumulation test tanks for simulated rainfall experiments to examine the runoff and sediment yield disparities between pure accumula-tion and accumulation with 20％gravel content under varied rainfall conditions.The findings revealed the following:1)Gravel effectively delayed runoff initiation on accumulation slopes,exhibiting an average delay benefit of 299.56％.Throughout the rainfall process,both pure and mixed soil and gravel accumulations demonstrated a simi-lar increasing trend in runoff rate with prolonged runoff generation duration.The average runoff rate escalated by 34.48％-244.83％with rising rainfall intensity.In comparison to pure accumulation,mixed soil and gravel accumu-lation displayed a decrease in average runoff rate by 6.54％-45.83％,along with a reduction in average flow veloci-ty by 13.76％-30.54％.2)The erosion rate of both pure and mixed soil and gravel accumulations generally exhibi-ted a gradual increase or tended to stabilize with runoff generation duration under rainfall intensities below 1.5 mm/min.The average erosion rate of mixed soil and gravel accumulation was 80.39％-84.95％lower than that of pure accumulation.However,under heavy rainfall conditions(2.0 mm/min),the erosion rate of pure soil accumulation experienced rapid escalation followed by a decline,while that of mixed soil and gravel accumulation increased in a fluctuating manner,with the average erosion rate 20.04％higher than the former.3)Both rainfall intensity and gravel content significantly influenced runoff,sediment yield,and flow velocity on accumulation slopes,indicating notable differences overall(P＜0.05).The overall trend displayed an increase in both water and sediment.These results offer scientific guidance for implementing measures against soil erosion in production and construction pro-jects involving accumulations,and provide fundamental data for establishing soil erosion prediction models for accu-mulation engineering.
关键词
红壤堆积体/模拟降雨/产流产沙/流速/土石混合
Key words
red soil accumulation/simulated rainfall/runoff and sediment yield/runoff velocity/mixed soil and gravel
维普
万方数据