反滤压重及埋深对深厚覆盖层允许坡降影响研究
Influence of weights and buried depth on the allowable hydraulic gradient of deep overburden foundation
张会豪 1邱子源 1金伟 2张丹 3罗玉龙1
作者信息
- 1. 河海大学水利水电学院,江苏南京 210024
- 2. 河海大学水利水电学院,江苏南京 210024;中国电建集团成都勘测设计研究院有限公司,四川成都 610072
- 3. 中国电建集团成都勘测设计研究院有限公司,四川成都 610072
- 折叠
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.
Abstract
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 soil ③-1 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.
关键词
深厚覆盖层/允许坡降/反滤压重/埋深/应力状态Key words
deep overburden foundation/allowable hydraulic gradient/weights/buried depth/stress state引用本文复制引用
基金项目
国家重点研发计划(2017YFC1502603)
国家自然科学基金(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项目(islJCTD-2022-2)
湖南省水利科技项目(XSKJ2021000-35)
湖南省水利科技项目(XSKJ2022068-37)
出版年
2024
国家科技期刊平台
NSTL
万方数据