Effect of seawater for mixing and curing on structural concrete

TLDR

The study investigates how mixing and curing concrete with seawater affects its compressive, tensile, flexural, and bond strengths. Concrete mixes were prepared by varying coarse aggregates, cement proportions, and types, with six groups mixed and cured in fresh water, six in seawater, and four mixed in fresh water but cured in seawater. Concrete mixed and cured in seawater shows increased strengths up to 14 days, but strengths decline after 28 days, with the decline worsening over time due to salt crystallization.

Abstract

In this article, the effects of mixing and curing concrete with seawater on the compressive, tensile, flexural and bond strengths of concrete are investigated. Concrete mixes were prepared by varying coarse aggregates, cement proportions and types. Six groups of concrete mixes were mixed and cured in fresh water, six groups were mixed and cured in seawater, while four groups were mixed with fresh water and cured in seawater. The compressive strength and subsequently the other related strengths of concrete were shown to increase for specimens mixed and cured in seawater at early ages up to 14 days, while a definite decrease in the respective strengths was observed for ages more than 28 days and up to 90 days. The reduction in strength increases with an increase in exposure time, which may be due to salt crystallisation formation affecting the strength gain.