坡高及坡比对渠道边坡可靠度的影响  

Influence of Slope Height and Slope Ratio on Reliability of Channel Slopes

作　　者：朱磊 高欣悦 万愉快 ZHU Lei;GAO Xinyue;WAN Yukuai(Ningxia University,Yinchuan 750021,China;Key Laboratory of the Internet of Water and Digittal Water Governance of the Yellow River,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学,银川750021 [2]宁夏大学宁夏回族自治区黄河水联网数字治水重点实验室,银川750021

出　　处：《灌溉排水学报》2023年第12期125-131,共7页Journal of Irrigation and Drainage

基　　金：国家自然科学基金(51879134);宁夏重点研发项目(引才专项)(2020BEB04004);宁夏回族自治区重点研发计划项目(2021BEG03023);宁夏高等学校一流学科建设(水利工国家自然科学基金程)资助项目(NXYLXK2021A03)。

摘　　要：【目的】探讨坡高和坡比对渠道边坡可靠度的影响,为渠道边坡的优化设计提供科学依据。【方法】利用Karhunen-Loève(K-L)展开法建立土体参数的二维随机场模型,使用简化的Bishop法计算渠道边坡的安全系数,通过Monte Carlo模拟渠道边坡的失效概率和可靠度指标,分析坡高和坡比对渠道边坡可靠度的影响。【结果】不考虑和考虑土体参数的空间变异性时,可靠度指标均随坡比的增大而减小;不考虑土体参数的空间变异性时,可靠度指标随坡高的增大而逐渐减小,但在粘聚力变异系数较大而内摩擦角变异系数较小时,可靠度指标呈现随坡高增大而增大的特殊现象;考虑土体参数的空间变异性时,在粘聚力变异性较小而内摩擦角变异性较大时,可靠度指标随坡高的增大而减小,其他情况均呈现随坡高的增大而增大的特殊现象。【结论】相对于降低坡高而言,采取减小坡比的措施可以更好地保障边坡可靠度,降低渠道边坡工程风险。【Background】Slope height and slope ratio are the most important design parameters affecting slope stability.This paper investigates their combined impact on reliability of channel slopes in attempt to help optimize design and remediation of such slopes.【Method】The spatial variation of soil cohesion was calculated using the Karhunen-Loève(K-L)expansion method.With spatial variation of soil cohesion considered,the safety factor was calculated using the simplified Bishop method.The failing probability of the slope was calculated by the Monte Carlo simulation,from which we analyzed the influence of slope height and ratio on slope reliability.【Result】The reliability index gradually decreased with the increase in slope ratio.Regard less of spatial variability of the soil strength parameters,the reliability index gradually decreased with the increase in slope height.When the coefficient of variation of the cohesion was large and the coefficient of variation of the internal friction angle was small,the reliability index increased with the increase in slope height.Considering spatial variability of soil mechanical parameters,the reliability index increased with the increase in slope height,except when the variability of the cohesion was small and the variability of the internal friction angle was large.【Conclusion】In comparison to reducing slope height in exchange for slope stability,reducing the slope ratio was more effective in improving slope reliability and minimizing engineering risks.

关 键 词：渠道边坡 可靠度分析 坡高 坡比 极限平衡 

分 类 号：TV91[水利工程—水利水电工程]