核电厂大体积混凝土取水管廊裂缝原因及控制措施
2021-07-22黄卫兵
黄卫兵



摘 要:本文以某核电厂地下大体积混凝土结构取水管廊为研究对象,探讨大体积混凝土浇筑后产生裂缝的原因,并对其进行修复处理,研究总结了施工工序控制措施。结果表明,裂缝是施工过程中温度变化、施工工艺等各类因素综合作用的结果。为此,在混凝土浇筑、养护、拆模、温度监测等施工工序中,要采取合理的控制措施,以有效控制裂缝的产生,保证工程质量。
关键词:大体积混凝土;裂缝;取水管廊
中图分类号:TU758.1文献标识码:A文章编号:1003-5168(2021)08-0105-04
The Causes and Treatment Methods of Cracks in Mass Concrete
Intake Pipe Gallery of Nuclear Power Plant
HUANG Weibing
(Shanghai Nuclear Engineering Research & Design Institute Co., Ltd.,Shanghai 200233)
Abstract: Taking the underground water intake pipe gallery with mass concrete structure of a nuclear power plant as the research object, this paper discussed the causes of cracks after the mass concrete pouring, and carried out the repair treatment, and studied and summarized the construction process control measures. The results show that the crack is the result of the comprehensive effect of various factors such as temperature change, construction technology and so on. Therefore, in the construction process of concrete pouring, curing, formwork removal and temperature monitoring, reasonable control measures should be taken to effectively control the generation of cracks and ensure the quality of the project.
Keywords: mass concrete;cracks;intake gallery
核電厂循环水系统的主要功能是向常规岛汽轮机凝汽器及其辅助设备提供冷却水,并向核岛厂用水系统提供冷却服务。因此,循环水取水管廊施工质量的好坏直接影响核电厂运行期间的安全。目前,国内核电施工企业对于类似循环水取水管廊等结构较复杂的大体积混凝土有着比较丰富的施工经验,但是,施工是结构体系、荷载、温度、时间、边界条件都不断变化的过程,原材料、配合比、施工方法、建筑物结构、设计等各种因素都会影响施工阶段的质量和使用阶段的性能。本文通过对某核电厂地下大体积混凝土结构取水管廊浇筑后产生裂缝的原因进行分析,得出裂缝主要是由温度变化及施工工艺不合理等导致的。同时,提出了裂缝修复处理措施。
1 案例介绍
管廊设计及施工情况:该管廊为外方内圆的现浇钢筋混凝土管,内圆直径为3.8 m,管壁厚度为600 mm;采用C40混凝土防水险,抗渗标号为W12,抗冻标号为F300,标准段长为25 m;相邻段之间设伸缩缝,缝宽为2 cm;取水管工作压力为0.14 MPa,运行时管内流体为海水。……
