Application of C50 negative temperature concrete in bridge engineering

Because C50 concrete with antifreeze admixtures has not been used in bridge engineering in cold weather areas, this paper focuses on how to avoid damage from early-age freezing for C50 concrete. First of all, compressive strength and frost resistance test of C50 concrete with antifreeze admixtures were researched in the conditions of -10¢C. The concrete mix proportion was optimized, and the critical frozen compressive strength was 15.6MPa, and the critical frozen compressive strength subjected to freezing and thawing was 26MPa. According to the research results of the effect of antifreeze admixtures on concrete durability in the laboratory, the concrete mix proportion for girders of Harbin Yang Ming Beach Bridge in winter construction was determined, and various technical measures were adopted, such as temperature controlling of concrete casting and curing. The field application of C50 concrete for girders at negative temperature was successfully completed.