高塔清水混凝土的抗裂耐久性协同提升技术与应用

Application and Coordinated Promotion Technology of Crack Resistance and Durability of Tower Fair-faced Concrete

针对虎门二桥坭洲水道桥索塔清水混凝土高程泵送、大体积混凝土的温控防裂和外观质量要求高的特点,对清水混凝土用原材料进行了优选,开发了高塔清水混凝土专用外加剂和匀质性提升技术,制备出了自密实抗裂和高耐久的主塔清水混凝土,在此基础上对主塔清水混凝土模板体系进行了优选,在大量模型试验的基础上提出本工程主塔混凝土施工质量控制关键点,并将研究成果直接应用于主塔清水混凝土施工,现场应用效果良好、达到了预期目标,为类似工程的施工提供了有益的借鉴。

Aiming at the characteristics of concrete of Nizhou Waterway Bridge in Humen,such as high pumping height,temperature control of mass concrete and high requirements of appearance quality,the raw materials were optimized,and special additive as well as homogeneous lifting technique were developed,thus the selfcompacting,anticracking and high durability of main tower airfaced concrete was prepared. On the basis of these,the optimization of formwork system was carried out,and the key points of construction quality control on this project were proposed according to a large number of model tests. The research results were applied directly to the construction of the main tower airfaced concrete. The good effect of field application provides a useful reference for the construction of similar projects.