Title |
Chloride Diffusion Coefficient at Reference Time for High Performance Concrete for Bridge Pylons in Marine Environment
|
Keywords |
고성능 콘크리트 ; 기준재령 염소이온 확산계수 ; 광물질 혼화재 ; high performance concrete ; chloride diffusion coefficient at reference time ; mineral admixtures |
Abstract |
High performance concrete mixes are selected and corresponding test specimens are made for the study of chloride diffusion coefficient at reference time. The concrete mixes were same designs as those used in construction of bridges located in a marine environment. Mix design variables included binder type, water-to-binder ratio, mineral admixtures to total binder weight substitution ratio, fine aggregate source, chemical water reducer admixture type for high strength and high flowability, and target slump or slump flow. The test results showed that the diffusion coefficients at reference time varied significantly according to the type of mineral admixtures and their substitution ratios. A model for diffusion coefficient at reference time considering the type of mineral admixture and the substitution ratio was developed. Diffusion coefficients from the developed model were compared with those from literature review, a previous model, and additional test results. All of the comparisons verified that the developed model can reasonably predict diffusion coefficients and the application of the model to the durability design against chloride penetration is appropriate.
|