The focus of this study is to investigate the ASR of concrete incorporating pre-treated soda-lime glass as aggregates. The glass aggregates were pre-treated with three different techniques, i.e. Ca(OH)2, NaOH and the mixed solution. The results indicate that all the pre-treatment techniques showed a decrease effect on ASR and such an effect increase with treatment time, the mixed solution showed the best effect. The pre-treated glass aggregate at the mixed solution at 80℃ for 7 days providing a 45% reduction in the expansion caused by ASR, and it can be considered innocuous based on ASTM C1260.
This research provides optimization techniques for concrete mixture design for chloride penetration performance and cost. For optimization, objective functions are constructed with variables representing factors used in concrete mixture design process. Multi Objective Harmony Search Algorithm (MOHSA) is used for optimization and the result gives relationship between concrete’s chloride ion diffusivity and cost.
This paper presents an improved double diffusion model (DDM) for the alkali silica reaction. By this model we could simulate the diffusion process of alkali both in concrete (macro-scale) and aggregate (micro-scale). As the alkali source, either internal or outside cases can be analyzed through this model. Concrete with different size groups of aggregate distribution also can be analyzed. Numerical simulation is utilized to analyze the ion concentration both inside the concrete and aggregate at different moment of penetration.