中国农村水利水电Issue(1)：168-172,179,6.DOI:10.12396/znsd.2500218
深厚黏性土地基上建高围堰设计关键技术问题
Key Technical Issues in the Design of High Cofferdams on Deep-seated Cohesive Soil Foundations
田应辉 1王迎 2吴文洪 2侯树芃 1徐海亮2
作者信息
- 1. 中国华电集团金沙江上游水电开发有限公司,四川 成都 610041
- 2. 中国电建集团中南勘测设计研究院有限公司,湖南 长沙 410014
- 折叠
摘要
Abstract
The overburden of the cofferdam foundation at the Lawa Hydropower Station contains a 50 m-thick lacustrine sediment low-liquid-limit clay layer,characterized by large thickness,low bearing capacity,low permeability coefficient,and low shear strength.Rapid filling and loading of the cofferdam generate excess static pore water pressure in the saturated cohesive soil of the foundation,reducing soil shear strength and causing stability issues for the 130m-high combined high slope formed by the cofferdam and foundation pit excavation,as well as significant deformation of the cofferdam.Through research and field tests,ultra-deep gravel piles with a depth of 70 m were used for the first time to reinforce the soft foundation,accelerating soil drainage and improving the deformation modulus and shear strength of the composite foundation.This paper focuses on the key technical issues encountered in the analysis of slip resistance and deformation stability of the composite foundation.It is recommended to use the limit equilibrium method for slip stability calculations,with shear strength indices determined according to different components and calculation conditions.For saturated cohesive soils,the adverse effects of excess pore water pressure should be noted,and the time-history variation of excess pore water pressure should be analyzed.The shear strength of the composite foundation can be obtained through area-weighted analysis,and the composite permeability coefficient can be derived based on the similarity principle of consolidation degree.This paper introduces the foundation treatment scheme and construction of the Lawa cofferdam,providing reference for similar projects.关键词
拉哇/深厚覆盖层/超静孔隙水压力/超深碎石桩/复合地基Key words
Lawa/deep overburden/excess pore-water pressure/ultra-deep gravel pile/composite foundation分类
建筑与水利引用本文复制引用
田应辉,王迎,吴文洪,侯树芃,徐海亮..深厚黏性土地基上建高围堰设计关键技术问题[J].中国农村水利水电,2026,(1):168-172,179,6.
