Strength and durability parameters of an environmentally friendly concrete

Abstract

Due to the significant environmental impact that the concrete production causes, and as a contribution to sustainability of this industry; presently sorne of the concrete constituents are replaced with alternative recycled materials. Chloride ingress into concrete is one of the main causes of electrochemicaJ corros ion of reinforcement. Although there is an interest to use Recycled Concrete Aggregate (RCA) in concrete, its use is limited due to its detrimental effect on durability. Therefore in this research RCA and Supplementary Cementing Materials (SCM), such as Fly Ash (FA) and Silica Fume (SF), were used to produce durable and environmentally friendly concretes. They were evaluated based on Iheir compressive strength, porosity, electrical resistivity and chloride-induced reinforcement corrosion when Ihey were exposed lo accelerated chloride conditions. The corrosion rates of steel embedded in these concretes were measured by the electrochemical impedance spectroscopy technique. The results indicaled that concrete manufactured with 100% RCA are inferior to conventional concretes, but their performance can be improved by replacing Portland cement by 30% FA ev'lO% SE