三板溪面板堆石坝坝体变形控制

Dam deformation control of concrete faced rockfill dam of Sanbanxi Hydropower Project

对面板堆石坝而言,坝体变形控制是设计和施工的首要问题。三板溪水电站主、副坝均为面板堆石坝。主坝最大坝高185.5m,建于峡谷河段,筑坝材料为超硬岩及强风化料,岩性复杂,填筑工期短;副坝最大坝高92.1m,上下游均为贴坡坝型,坝基地形特殊,以上条件对控制坝体变形均不利。在设计中,从坝基开挖处理、坝料选配、坝体分区、填筑要求、施工程序和进度安排等方面均采取了措施,以减少这些不利影响,保证大坝安全运行。

For the concrete faced rockfill dam, the deformation control is the key to the design and construction. The main dam and the secondary dam of Sanbanxi Hydropower Project are all concrete faced rockfill dam. The main dam has a maximum height of 185.5 m, built in the narrow reach. The dam materials are super-hard rock and intensely-weathered rock with complex lithology and the short filling duration. The secondary dam has a maximum height of 92.1 m, with special topographic conditions of dam foundation. The upstream and downstream ofdam are all placed close to the slopes, All of above conditions are adverse to the dam deformation control. In order to assure operation safety of the dam, a series of measures on dam foundation excavation, dam material selection and gradation, dam body zoning, rockfill, construction procedures and schedules have been adopted in the design to decrease these adverse influences.