Admixtures Used in Self-Compacting Concrete: A Review

Abstract

Self-compacting concrete or self-consolidated concrete is a highly flowable, non-segregating concrete which spreads into congested reinforcement area and fills the formwork without the use of any vibrators. Self-compacting concrete allows denser reinforcement, optimized concrete section and shapes, and greater degree of freedom. It has the advantages of maintaining the durability and characteristics and meeting expected performance requirements. It has been used ideally in bridges, drilled shaft, and earth-retaining structure, columns and area with high concentration of rebars and pipes. The self-compacting concrete improves constructability, reduces skilled labor and noise level, minimizes the voids in highly reinforced area, gives superior strength and durability and smooth and uniform surface finishing and accelerates the project schedules. In the present study, various mineral admixtures, i.e., ground-granulated blast-furnace slag, limestone powder, silica fume, fly ash and chemical admixtures such as sulfonated melamine formaldehyde condensate, melamine formaldehyde, sulfonated naphthalene formaldehyde condensates and polycarboxylate ether-based superplasticizer, have been studied in the self-compacting concrete. A critical review of the effect of combination of these mineral and chemical admixtures on various rheological, strength and durability properties of the self-compacting concrete is presented in this paper.