港珠澳大桥环岛挡浪墙素清水混凝土裂缝控制技术研究

港珠澳大桥东人工岛护岸挡浪墙属于大体积素清水混凝土长墙结构,内部无钢筋。在分段长度为9 m前提下,通过足尺寸模型研究挡浪墙裂缝发展规律,并寻求有效的裂缝控制技术。试验结果表明:不采取内部降温措施情况下,挡浪墙体的内部温升为45.9 ℃,应变为126×10^-6,墙体出现3条裂缝;墙体内布设1层和2层冷却水管情况下,内部最高温度分别降低9.2 ℃和14.1 ℃;墙体内布设2层冷却水管,控制侧墙与底板浇筑间隔时间不超过10 d,墙体无裂缝产生。

Study on crack control technology for fair-faced concrete of the protection wall in the east artificial island of HongKong-Zhuhai-Macao Bridge

The protection wall in the east artificial island of Hongkong-Zhuhai-Macao Bridge is a mass concrete structure,also long wall structure. Supposing the length of the wall is 9 meters,the paper researches the development law of cracks in the retaining wall through full-scale model test,and researches effective crack control technology. The research results show that:without internal cooling control measures,the internal temperature rise of the wall is 45.9 ℃ and the strain is 126×10^-6. At the same time,there will be three cracks in the wall. The highest temperature inside the wall is reduced by 9.2 ℃ by placed one layer of cooling water pipe,and reduced by 14.1 ℃ by placed two layers of cooling water pipe. When two-layer cooling water pipes are arranged in the wall and the construction time interval between the bottom plate and the wall is not more than 10 days,there is no crack in the wall.