USE OF WOODASH IN NON-AUTOCLAVED AERATED CONCRETE
Keywords:
Autoclave, Aerated, Density, Compressive strength, Aluminium powder, Lightweight, Woodash.Abstract
Non Autoclaved aerated concrete is a lightweight environmental friendly construction material. They are used as masonry units. They are made using a mixture of sand/woodash, cement, lime powder, gypsum powder, aluminium powder and water. Woodash is the residue left after burning wood and is different from flyash. Aluminium powder is mixed in small proportions by weight of the dry materials. Aluminium powder is responsible for forming gas bubbles in the mix resulting in the formation of lightweight aerated concrete. Water to dry materials ratio is taken as 0.6. Instead of rapid curing in an autoclave, conventional curing method of immersing in water was used to save energy costs. The amount of aluminium powder added to the mixture can be altered to produce samples of varying densities. But increase in aluminium powder content leads to decrease in compressive strength of samples.
