Title: Fresh, Mechanical, and Durability Characteristics of Self-Consolidating Concrete Incorporating Recycled Concrete Aggregate

Author(s): Yasser Khodair and Bhagiratha Bommareddy

Publication: Symposium Paper

Volume: 314

Issue:

Appears on pages(s): 1-20

Keywords: Self-consolidating concrete; Cementitiuous Materials; Shrinkage; Recycled Concrete Aggregate; Fly ash, Slag, fresh properties, hardened properties

DOI: 10.14359/51689736

Date: 3/1/2017

Abstract:
This paper studies the fresh, hardened, and durability characteristics of Self-Consolidating Concrete incorporating Recycled Concrete Aggregate (SCCRCA). Twenty concrete mixtures were divided into five different groups, with constant water to cementitious materials ratio of 0.38, based on the Recycled Concrete Aggregate (RCA) content: 0, 25, 50, 75, and 100% of natural coarse aggregate (NCA) replaced by RCA. All mixtures were designed to have slump greater than 500 mm (19.7 in). The Portland cement was substituted by different percentages of Fly Ash (FA) and Ground Granulated Blast Furnace Slag (S), while the control mixtures were prepared using 100% Portland cement. The fresh concrete properties of all mixtures were investigated, such as: flowability, deformability; filling capacity, and the ability to resist segregation. Moreover, the compressive strength at 3, 14, and 28 days, the tensile strength, and the free shrinkage up to 80 days were studied. Partial replacement of Supplementary Cementitious Materials (SCMs) for cement reduced the 28-days-compressive strength of SCCRCA mixtures compared to those of the control mixtures. Based on the outcomes of this research, replacing the natural coarse aggregate (NCA) in SCC by more than 75% RCA is not recommended. However, this percentage might change depending on a variety of factors.