Experimental Investigation into the Freeze-Thaw Resistance of Concrete Using Recycled Concrete Aggregates and Admixtures

Abstract

This work investigates the effects of recycled concrete aggregates on the freeze-thaw resistance of the concrete. Taguchi orthogonal optimization technique was used in this investigation in order to minimize the number of samples required for each experiment. Therefore, only a few combination values of control factors required were chosen. Orthogonal table with three levels and four factors was used to prepare the mixing proportions. The results were analysis to check interaction among the factors. The results showed that in saturated Recycled Aggregate Concrete (RAC), the recycled aggregate has negative effects on its durability performance, therefore their use in structures exposed to severe climate is not strongly recommended. However, with the use of mineral and chemical admixtures, particularly air-entraining admixtures and fly ash, the recycled aggregate concrete could exhibit some level of durability.