超大断面预制沉管混凝土裂缝控制技术  

Crack control technology for concrete of super-large section precast immersed tube

作　　者：李进辉[1,2] 李阳 刘可心[1,2] 屠柳青[1,2] 张国志[2] 

机构地区：[1]中交武汉港湾工程设计研究院有限公司,湖北武汉430040 [2]长大桥梁建设施工技术交通行业重点实验室,湖北武汉430040 [3]中交二航局第二工程有限公司,重庆401120

出　　处：《混凝土》2014年第4期146-151,共6页Concrete

基　　金：国家科技部科研院所技术开发研究专项(2011EG124276)

摘　　要：港珠澳大桥超大断面预制沉管混凝土强度等级高、结构尺寸大,工程区域气候炎热、腐蚀环境恶劣,控裂要求高、难度大。在温度应力仿真分析的基础上开展温控设计,现场采取优选原材料、优化配合比、控制原材料温度、片冰和制冷水拌和混凝土、喷雾降温和养护、自动化温度监测等综合温控措施控制大体积混凝土温度裂缝。从监测结果来看,温度监测结果与仿真计算吻合,最高温度和内表温差均在温控标准范围内。从现场情况来看,预制沉管未出现有害温度裂缝,温控效果良好,达到了预期的温控目标。As the complex structure, large size, hot climate, aggressive corrosive environment and high concrete strength grade for su-per-large section precast immersed tube of hong kong-zhuhai-macao Bridge, crack control of concrete was difficult.On the basis of simu-lating analysis on thermal stress,temperature control design was carried out.Harmful crack could be effective controlled by series of treat- ment measures during consmaction period such as optimization of raw materials,preparation of low heat and shrinkage concrete, control- ling concrete raw material temperature, mixing concrete with ice shavings and cooling water, setting up automatic maintenance system and automatic temperature monitoring system.From the monitoring results, the temperature monitoring results were consistent with the simula-tion data, and the maximum temperature and the temperature difference between concrete surface and internal concrete were met the re-quirement of temperature control standard.Moreover, precast immersed tube didn＇t appear harmful crack.

关 键 词：超大断面 预制沉管 混凝土 温度裂缝 控制技术 片冰拌和 

分 类 号：TU528.07[建筑科学—建筑技术科学]