Use of Steel Slag and/or Air Pollution Control Devices Dust as Filler in the Manufacture of Fly Ash Bricks

Conventional bricks made of clay are the basic component used for construction proposes around the world.Waste materials like Fly ash, steel slag and APCD dust have adverse impacts on human health and is a cause of concern. For environmental protection and sustainable development, there is a need to explore the use of such waste materials in manufacturing of fly ash bricks. The present study focussed on the assessment of use of steel slag and/or APCD dust as fillers in fly ash bricks in order to increase strength of bricks and to facilitate the use of steel slag or APCD dust which are considered to be hazardous wastes. The test bricks manufactured from steel slag, APCD dust and fly ash used in different proportions were subjected to tests including water absorption and compressive strength. Results showed significant decrease in water absorption up to 17% and increase in compressive strength up to 12 N/mm2 with 21% of steel slag in fly ash brick. APCD dust was also varied from 5 to 20% but due to its very fine size, it was unable to bond strongly enough with rest of the mixture, resulting in higher water absorption rate of 24.53%. As the fly ash possess good pozzolonic properties similar to cement, studies revealed that steel slag also possess comparable properties with those of natural aggregates and therefore it can be effectively used as filler in fly ash bricks.