孔口坝段高温季节施工温控防裂研究  

Study on temperature control and crack prevention ofholed dam section during high-temperature construction period

作　　者：郝志强[1] 唐忠敏[2] 刘毅[1] 

机构地区：[1]中国水利水电科学研究院结构材料所,北京100038 [2]中国水电顾问集团成都勘测设计研究院,四川成都610072

出　　处：《人民长江》2013年第15期34-37,共4页Yangtze River

摘　　要：针对高温季节施工的孔口坝段孔口部位的牛腿混凝土最高温度超标以及牛腿与坝体主体混凝土温差过大的问题,以某拱坝孔口坝段为例,用三维有限元仿真分析方法对其进行了研究。结果表明:虽然牛腿部位最高温度严重超标,但应力并未超标,其最大应力发生在牛腿与坝体交界处;孔口顶板混凝土较底板和侧墙有较大开裂风险,其应力主要为横河向应力。因此,牛腿相对于大坝主体混凝土而言,温度控制标准可适当放宽;可通过加大顶板第一层混凝土的厚度、减小顶板上层混凝土厚度的方法,达到减小顶板横河向超标应力的目的。In view of the peak temperature at bracket concrete of holed dam section exceeding the standard and excessive temperature difference between bracket and dam concrete during high-temperature construction period,we present a research on the holed section of an arch dam by 3D FEM simulation analysis.The result shows that the stress in bracket does not exceed the limit though its peak temperature seriously exceeds the standard,and the maximum stress appears at the junction between bracket and dam body.Dominated by transverse stress,the cracking risk of top slab concrete over hole is much higher than that of bottom slab and side wall.Therefore,the temperature control standard for bracket concrete can be lowered properly.In order to reduce the excessive transverse stress in top slab,two measures of increasing thickness of the first-layer concrete and reducing the thickness of the upper-layer concrete can be adopted.

关 键 词：绝热温升 水管冷却 温度场 温度应力 温控防裂 高温季节 

分 类 号：TV43[水利工程—水工结构工程]