Durability Aspects in Reference to Permeable Voids and Leaching of Calcium Hydroxide in Concrete with Quarrysand and Flyash

The concrete industry is constantly looking for supplementary cementitious material with the objective of reducing the solid waste disposal problem. Fly ash (FA) and Quarry sand (QS) are some among the solid wastes generated by industry. The Quarry sand is one such material which can be used to replace sand as fine aggregate. To overcome from this crisis, partial replacement of natural sand (NS) with Quarry sand and partial replacement of cement with FA can be an economic alternative. This research is carried to study the effect of replacement of sand by Quarry sand and cement by fly ash with using admixture in concrete, especially in reference to permeable voids development, compressive strength, leaching of Ca(OH)2 in curing water and RCPT at 28, 56 and 90 days of age. A M25, M30, M40 Grade concrete were chosen for research. The mix design was carried out and three combinations were chosen, first combination using 100% Natural sand and 100% cement ( treated as controlled mix).In second combination 100%Natural sand is replaced by Quarry sand and cement remains100%. In third combination 30% cement is replaced by Fly ash and 45% Natural sand is replaced by Quarry sand (treated as critical mix). These were chosen from 30 combinations of variable % of Natural sand and Quarry sand and fly ash. The study is aim at understanding the performance of critical mix in reference to controlled mix and concrete containing 100% quarry sand. It is observed that if quarry and is used for concrete then suitable percentage natural sand and fly ash must be added to achieve desired compressive strength and performance of concrete.