Tension stiffening behavior of ordinary Portland and geopolymer concrete: a review

Abstract

The contribution of concrete to carry tensile stresses between the primary cracks and stiffen the cracked member or the so-called "tension stiffening"- has gained a lot of attention among researchers. This is because tension stiffening significantly influences the cracking behavior and the deflection response of the structural member. Therefore, this paper aimed to summarize and discuss the findings on tension stiffening effects of both ordinary Portland concrete (OPC) and geopolymer concrete in order to give a clear understanding of cracking and deformation response of reinforced concrete at service limit state. This paper also emphasized various parameters that play a significant role in tension stiffening behavior including compressive strength of concrete (Fcu), concrete cover to bar diameter ratio (c/bd), reinforcement percentage (ρ %) and shrinkage. In general, most researchers have proved that fly ash geopolymer reinforced concrete exhibits less carbon footprints and considered a cheaper construction material compared to OPC. Moreover, it has comparable mechanical properties and so it can be fully incorporated for applications in civil engineering projects rather than OPC. Hence, this paper provided a comprehensive overview of state-of-the-art research on tension stiffening and its effects on crack behavior and deflection response of OPC and geopolymer concrete. The possibility of adopting tension stiffening approaches of OPC to be used for geopolymer concrete is also emphasized.