Effects of varying concentrations of chloride (Sodium Chloride) on the compressive strength of laterized concrete

Abstract

Compressive strength, one of the important characteristics of concrete can be influenced by different foreign materials present in the constituents of the concrete. This paper demonstrates the influence of sodium chloride (NaCl) on compressive strength of Laterised Concrete (LATCON). Several studies have established the effect of sea water on concrete strength but none of the study has categorically specified the level of concentration at which the strength is defective. This study bridge the gap by examining the variation of concrete compressive strength at different levels of concentrations of salt in the curing bath. The study used LATCON being a cost effective concrete. 72 concrete cubes were produced using 1:2:4 mix ratio with laterite as a fine aggregate. The cubes were cured in NaCl solution of varying concentrations from 0g/l to 50g/l at 10g/l intervals. The compressive strength of the laterized concretes was determined after 7, 14, 21 and 28 days. The results showed that compressive strength of the concrete increase with increase in curing age. The strength also increases with increase in salt concentration in the curing bath, upto 30g/l salt concentration and then starts to decrease. The study thus reveals that NaCl could have a deteriorative effect on the compressive strength of LATCON at higher concentrations. However, this does not pose a major threat if the concrete would be used as a lightweight concrete.