Mix design and properties of coral aggregate concrete for Oceania islands

Manufacturing concrete with coral gravel and coral sand as aggregates is of great significance for the construction in islands due to shortage of conventional aggregates. Research in this area is very scarce and mix design guidelines are not available for the concrete manufacturers and constructors. This paper presents mix design proportions and mechanical properties of concrete mixes containing coral aggregate obtained from an Oceania island. The properties of aggregates were measured in the lab to develop a mix design for 25MPa concrete strength which is commonly used in low rise and medium risebuildings. Stress-strain curves, modulus of elasticity and strength of coral concrete for the batched cylinders manufactured according to the proposed mix design are reported. An average strength of 27MPa was determined for the trial mix. The mix design for various other strengths of coral aggregate concrete was then developed. The findings of this research are useful for the designers and contractors of Oceania islands