新疆某工程碾压混凝土坝施工期温控防裂

Temperature control and crack prevention of a RCC dam during construction in Xinjiang

新疆某水利枢纽工程地处严寒干旱地区,挡水建筑物为碾压混凝土重力坝,最大坝高75.5 m,总库容2.94亿m^3,属大(2)型工程。典型严寒地区“冷”、“热”、“风”、“干”的不利气候因素和长间歇式的施工方式增加了坝体混凝土的温控防裂难度。通过从设计到施工采取一系列温控措施,包括控制浇筑温度、优化水管冷却、坝面永久保温、仓面和其他临空面春秋季临时保温和越冬保温、优化浇筑计划等,大大降低了大坝混凝土的开裂风险,大坝混凝土的温度裂缝得到了有效控制。

A water conservancy project in Xinjiang is located in a cold and arid area. The water retaining structure is a RCC gravity dam with a maximum height of 75.5 m, and the total storage capacity is 294 million m^3. The unfavorable climate, namely cold, hot, windy and dry in typical severe cold region and the intermittent construction method have increased the difficulty of temperature control and crack prevention of dam concrete. By taking a series of temperature control measures from design to construction, including pouring temperature control, pipe cooling optimization, permanent thermal insulation of dam surface, temporary thermal insulation in spring and autumn and overwintering thermal insulation of the lift surface and other exposed surfaces, and pouring plan optimization, the cracking risk of dam concrete has been substantially reduced, and the temperature cracks of dam concrete have been effectively controlled.