摘要
反滤压重及埋深均会影响土体允许坡降,但目前尚无法量化这些影响。量化反滤压重及埋深的影响是合理确定允许坡降,科学评价坝基渗流安全的关键。采用轴向应力模拟反滤压重及埋深的作用,针对泸定水电站下游坝基(3)-1层,开展了(3)-1层级配包络线在不同轴向应力条件下的渗透试验,量化了反滤压重及埋深对(3)-1层临界坡降的影响。结果表明:随着轴向应力的增大,(3)-1层上包线和平均线土体的临界坡降呈线性增加趋势,而下包线土体的临界坡降受轴向应力影响很小。基于试验结果,量化了反滤压重和埋深对(3)-1层允许坡降的贡献,建立了随轴向应力变化的(3)-1层土体允许坡降公式,提出了可考虑反滤压重措施及土体埋深影响的允许坡降建议取值方法,该方法可供后续类似工程借鉴采用。
Both weights and buried depth can influence the allowable hydraulic gradient of soil,but these effects have not been quantified.Quantification of these influences is the key to determine the allowable hydraulic gradient and to evaluate seepage safety.In this study,the axial stress was adopted to simulate the effects of weights and buried depth.A list of seepage tests under different axial stresses was performed on soil③-1 of Luding Hydropower Station,and the influences of weights and buried depth on the critical hydraulic gradient were quantified.The results indicate that the critical hydraulic gradients of the upper and middle envelopes of particle size distribution linearly increase with the increase in axial stress,while that of the lower envelope is not influenced by the axial stress.The influences of weights and buried depth on the allowable hydraulic gradient were quantified based on the experimental results,and a formula describing the variation of the allowable hydraulic gradient with axial stress was proposed,and then a method determining the allowable hydraulic gradient which can consider the influences of weights and buried depth was established,and it can provide a reference for the similar project.
作者
张会豪
邱子源
金伟
张丹
罗玉龙
ZHANG Hui-hao;QIU Zi-yuan;JIN Wei;ZHANG Dan;LUO Yu-long(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing,Jiangsu 210024,China;Power China Chengdu Engineering Corporation Limited,Chengdu,Sichuan 610072,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2024年第3期769-776,共8页
Rock and Soil Mechanics
基金
国家重点研发计划(No.2017YFC1502603)
国家自然科学基金资助项目(No.51679070)
中国科学院青海盐湖研究所基础研究青年创新交叉团队(No.islJCTD-2022-2)
湖南省水利科技项目(No.XSKJ2021000-35,No.XSKJ2022068-37)。
关键词
深厚覆盖层
允许坡降
反滤压重
埋深
应力状态
deep overburden foundation
allowable hydraulic gradient
weights
buried depth
stress state
