某公路大桥箱梁用高性能混凝土配合比设计

The mix proportion design of high performance concrete in box beam of a certain bridge

以某特大公路桥现浇箱梁工程为背景,根据其所处南方湿热地区淡水环境的耐久性要求,采用高效减水剂和矿物细掺料双掺技术,通过配合比优化设计成功配制C60泵送高性能混凝土,并对其干燥收缩、抗氯离子渗透和抗碳化等耐久性能进行分析。结果表明,配制的高性能混凝土28 d干燥收缩值0.028 3%,电通量887 C,碳化深度0.58 mm,具有良好的耐久性能。

According to the environmental conditions of an actual engineering case of cast in-site box beams in a certain bridge which is in south moist heat areas of China, the C60 high performance pumping concrete was prepared by adding fly ash, slag and superplasticizer. And the dry shrinkage, the ability to resist chloride ion penetration and the carbonation resistance were investigated. The results show that the concrete cured by standard condition for 28 d has good durability, and the dry shrinkage quantity is less than 0.03% , the electric flux is 887 C, and the carbonation depth is 0.58 mm.