Evaluation of durability property of recycled concrete sand from waste concrete

Abstract

Due to the increase in the economic development of the infrastructure (road, bridge, flyover, subway, etc.), the increasing quantity of demolition waste and the lack of natural resources, the environmental conditions have reached an alarm stage in the metro cities. In many metro cities of India, there is a heap of construction and demolition waste on road side, which is the perfect source of aggregates and sand for making concrete. Many researchers used the recycled concrete aggregate and sand to make concrete and it was found that recycled aggregate and recycled sand produced from waste concrete can be used in road and building construction. This research paper examines the changes in the properties of fresh and hard state of concrete made from Recycled concrete sand (RCS). It has been studied by comparing concrete made with 20%, 40%, 60%, 80% and 100% recycled concrete sand with control concrete (R-0 concrete) that was designed for M 40 Mpa compressive strength and 4.5 Mpa flexural Strength and the results indicated that the concrete made from RCS is workable in conjunction with control concrete, but the mechanical properties of concrete (compressive strength, flexural strength, split tensile strength and modulus of elasticity) and durability properties (dry shrinkage, Soroptivity and abrasion) of 60% RCS mixed concrete are comparable to control concrete. In which the dry shrinkage of R100 concrete at 28-day curing was two times as well as greater amount of abrason as compared to the controled concrete and during its soroptivity test, the soroptivity coefficient at the initial stage (<7 hours) decreases 41% and after 1 day it remains up to 11.3% in compression to controled concrete. The results show that the durability and stability of concrete made from recycled concrete sand is comparable to the control concrete.