Durability of Steel Reinforced Concrete Using Limestone, Sea Sand and Seawater in Concrete Mix

Abstract

Seawater and sea sand have potential used in concrete. The use of limestone in the concrete has been increasing due to benefits as aggregate include good strength and low possibility of alkali-silica reaction. Hence, it is imperative to exploit seawater, sea sand and limestone in concrete particularly corrosion issues follow it. This study aims to evaluate the effect of limestone, seawater, and sea-sand for mixing concrete on the corrosion of reinforcing bar. The specimen used in this study was a concrete block with strength design of 25 MPa and plain reinforcing bar with 10 mm in diameter was embedded. The result of half-cell potential (HCP) will be compared with the result of visual observations for actual corrosion after HCP readings indicates the specimens has been corroded. The results showed that reinforcing bar in all specimens mixed with seawater and using 100% limestone mixed with plain water using sea-sand is estimated to be corroded and corresponding with the actual corrosion. Further, it can be observed the use of washed sea-sand combine with 50% of limestone and mixed with seawater potentially increase the strength of concrete up to 50%, however, the risk of corrosion as well.