Author(s): Kai Sun; Chunyu Liang; Dazhou Zhao
Linked Author(s):
Keywords: CFRD; Numerical analysis; Foundation treatment; Deep overburden; Hekoucun
Abstract: For Concrete-Faced Rockfill dams sitting on deep overburden, the dam foundation of low modulus may further enlarge the deformation of the rockfill zones, concrete plinth, cut-off wall, and concrete face during construction and reservoir filling, and this excessive deformation will cause leakage, even complete failure of the seepage control system, therefore, it is necessary to study the influences of the overburden foundation on the main dam and the seepage control system, and then design the foundation treatment scheme based on study results to ensure the dam safety during reservoir operations. The dam height of Hekoucun CFRD Project is 122. 5m, and the dam foundation mainly consists of alluvial and diluvium sand and pebble with boulders and mud, an average depth of 30m and a maximum depth of 41. 8m. The foundation has four weak continuous clayey interlayers and more than ten sandy lenses. After the comparison of CFRD on deep overburden with or without different foundation treatments using three-dimensional numerical simulation, this paper presents the conclusion of the improvement to the dam stress and the decrease of the joint deformation of different foundation treatments applied to the Hekoucun CFRD Project. The analysis indicates that the designed foundation treatments can improve the stress condition of the rockfill zones, concrete face, cut-off wall, connecting plate and decrease the joint deformation differently. Based on the above study, the foundation treatment effectiveness of the combination of jet grouting piles and dynamic compaction is better for the Hekoucun CFRD Project.
Year: 2013