Experimental study on the mechanical properties and structural performance of the rapid hardening concrete

Abstract

Rapid-hardening concrete (RHC) is becoming more popular as a cast-in-place jointing material in precast concrete bridges and buildings due to its high tensile strength and crack resistance. RHC’s technical properties are highly regarded due to the working conditions of mega projects. The study assessed the impact of modern modifiers on concrete in order to select a composition of rapid-hardening concrete (RHC) with superior mechanical properties. Following an analysis of previous studies by other authors, microsilica and a polycarboxylate ether-based chemical additive was chosen as basic modifiers in the manufacture of RHC. In addition, four reinforced rapid-hardening concrete beams were tested for operational reliability and durability after 3 days of casting. The structural performance of RHC beams was evaluated in comparison to normal concrete beam specimens, and it was determined that crack distribution, load deflection, reinforcement strains, ductility, and toughness were all important factors in the evaluation. RHC beams exhibit higher ductility, toughness, ultimate loads, and deformability than NC beams. The tensile strength analysis revealed a positive impact of RHC, but the shrinkage crack related to heat hydration was crucial.