Influence of rebar types on the service life of a coral aggregate concrete structure

The objective of this paper is to investigate the influence of rebar types on the service life of a coral aggregate concrete (CAC) structure. In the present work, the CAC was cast in a range of compressive strengths varying from 30 to 50 MPa. The chloride-diffusion parameters of the CAC were obtained by experiment. Moreover, the chloride (Cl⁻) threshold values (CTVs) of various rebars were collected from different literature sources. Based on the modified chloride-diffusion model, the service life of the reinforced CAC structure with different rebars was calculated and the influence of rebar types on the service life of different CAC structures was investigated. The results demonstrate that the service life of the CAC structure adopting a high-quality rebar with high CTV value is longer than that of the CAC structure using a low-quality rebar. Furthermore, there is a novel phenomenon that the desalinated seawater has a significant impact on the service life of CAC structures adopting low-quality rebars, while it has an insignificant effect on that of CAC structures using high-quality rebars. Therefore, high-quality stainless steel must be adopted in CAC structures to meet a design life of 50–100 years, whether the desalinated seawater is used in the CAC structure or not.