Study on Offshore Sand Use as Part of the Substitution of River Sand and M Sand

The purpose of the study is to test the physical, chemical and structural characteristics of dredged offshore sand and to evaluate the extent of partial use as a replacement for river sand and M sand. For testing the physical and chemical properties, experiments like Grading, determination of Chlorides, Shell content and Organic matters were done. For analyzing the Structural properties various experiments like Sieve analysis, Gap grading, determinations of Compressive strength, Flexural strength, Rapid chloride penetration test (RCPT), Water absorption test and Alkalinity test were done. The amount of chloride, shell content, organic content were as per the standards. The compressive strength and flexural strength of concrete with graded sand were found to be comparable to that of concrete with River sand or M Sand. The RCPT results show that the average current passing through the off shore sand was within the range specified by ASTM for conventional concrete. Water absorption of concrete specimens cast with offshore sand was less, compared to specimens cast with graded offshore sand. The alkalinity of all the concrete specimens with graded offshore sand was within the permissible limits. Offshore sand can be used for making concrete when partially replaced with river sand or M Sand.