糯扎渡水电站地下厂房蜗壳混凝土浇筑质量控制

针对糯扎渡水电站地下厂房机组单机容量大，工作水头高，水头变幅较大，蜗壳混凝土保温、保压浇筑要求等特点，分析了蜗壳浇筑质量控制的重点。蜗壳浇筑时产生的座环抬动、“阴角”部位的浇筑、温控防裂、浇筑强度高等是施工控制的重点、难点，经分析蜗壳混凝土采用“象限法”分层浇筑较为有利。根据拟定的浇筑方案，并采取其他相关措施，保证了蜗壳混凝土浇筑质量。

Quality control for concrete placement for spiral case of underground power house of Nouzadu Hydropower Station

In the light of the characteristics of large unit capacity,high operation water head and its large fluctuation of water level,thermal insulation and pressure keeping of spiral case concrete placement,the key quality control points of spiral case concrete placement are analyzed,including stay ring moving-up,"dead zone" placement,temperature control and crack prevention,high placement intensity and so on.Quadrant method was adopted in the layered placement.The rational construction scheme and other relevant measures are adopted to guarantee the concrete placement quality of spiral case.