REPLACEMENT OF RIVER SILICA (OR) SAND WITH ROCK DUST AT HIGHER GRADES
Keywords:
concrete, fine particles, super plasticizers, compressive strength, flexural strength.Abstract
In such a situation the Quarry rock dust can be an economic alternative to the river sand. Quarry Rock Dust can be defined as residue, tailing or other non-voluble waste material after the extraction and processing of rocks to form fine particles less than 4.75mm. Usually, Quarry Rock Dust is used in large scale in the highways as a surface finishing material and also used for manufacturing of hollow blocks and lightweight concrete prefabricated Elements.
This paper presents the feasibility of the usage of Quarry Rock Dust as 100% substitutes for Natural Sand in concrete. Mix design has been developed for M40 grade using design approach IS for both conventional concrete and quarry dust concrete. Tests were conducted on cubes and beams to study the strength of concrete made of Quarry Rock Dust and the results were compared with the Natural Sand Concrete. It is found that the compressive and flexural strength of concrete made of Quarry Rock Dust are nearly 10% more than the conventional concrete. Tests were also conducted on cubes and beams which are exposed to temperatures of 300°C for 1hr, 3hr durations respectively.
The results show that at a dosage 1.3% of super plasticizer by weight of cement the concrete made of quarry stone dust as fine aggregate attained low strengths when compared with other dosages (1% and 1.6%) in compression and flexure.
