三峡碾压混凝土围堰设计

三峡碾压混凝土围堰包括纵向围堰和横向围堰．混凝土总量为320．69万m3。纵向围堰全长1150．47m，混凝土量153．33万m3。在纵向围堰中部的坝身段碾压混凝土结构内首次实现通水冷却和接缝灌浆。横向围堰最大坝高115m，堰顶全长580m，混凝土量167．36万m3，必须在4个月内完成，2003年1月22日实现日浇筑碾压混凝土21066m3，最高月浇筑47．6万m3，日和月浇筑碾压混凝土强度均较以前的世界纪录提高近1倍。2003年4月16日浇至堰顶，2003年6月上旬和左岸大坝一起提前4年挡水，拦蓄库容147亿m3，使枢纽工程提前实现蓄水、通航、发电的目标。

Design of Three Gorges RCC cofferdam

The Three Gorges RCC cofferdam including longitudinal and transverse ones has a total volume of 3 206 900 m3. The longitudinal cofferdam is 1 150. 47 m long and has a volume of 1. 533 M m3 , and water cooling and joint grouting in concrete structure at the middle section of it were first applied in the world; the transverse cofferdam that should be placed within 4 months has a maximum height of 115 m with a crest length of 580 m and a volume of 1. 6736 M m3. The daily placement rate hit 21 066 m3 on Jan. 22, 2003 and the maximum monthly placement rate 476 000 m3 that all nearly doubled the world records. The RCC cofferdam reached up to the final design elevation on A-pril 16, 2003 and started to retain water in early June together with the left dam section 4 months ahead of the schedule, with a reservoir volume of 14. 7 bn m3. As a result, the objectives of reservoir impoundment, navigation and power generation could be achieved in advance.