金安桥水电站大坝碾压混凝土温度控制初步分析

RCC Dam Temperature Control Analysis of Jin'anqiao Hydropower Station

金安桥水电站位于金沙江中游河段,大坝碾压混凝土量约为264.8万m3,具有工程规模大、工期紧、施工要求高、需在高温多雨季节连续施工等特点。碾压混凝土采用的温度控制措施主要有:优化混凝土配合比、降低入仓温度(预冷骨料、加冷水加冰拌和、运输过程保温)、仓面喷雾形成小气候、及时摊铺碾压(以斜层碾压为主)、仓面保温、通水冷却、加强温度控制管理等。历经2007年高温季节和冬季,大坝外观及浇筑各仓号均无裂缝。

The Jin＇anqiao Hydropower Station is located in the middle reach of the Jinsha River. Its dam RCC quantity is about 2.648 million m3. It is large in project scale, short in construction period; high in construction requirement, and should be constructed in hot and rainy reason. Its RCC temperature control includes： optimized concrete mix proportion, reducing concrete placement temperature （such as pre-cooled aggregate, adding cool water or ice and heat isolation during transportation）, spray water for forming small climate, laying and rolling in time （taking inclined layer rolling as its main）, heat isolation in concrete surface, water cooling and strengthening temperature control management. The dam experienced high hot in summer and cool in winter in 2007 and no crack occurs in its appearance and all placement position.