Phase development and mechanical response of low-level cement replacements with wood ash and washed wood ash

Abstract

A significant increase is seen worldwide in the amounts of wood ashes (WAs) produced by the heating and power industry. This study investigates the potential utilisation of two different WAs as low-level cement replacements, in an untreated and a washed version. Phase development and mechanical response were investigated. Results indicated ettringite formation mainly to contribute to the strength development until excessive formation. Indications of an optimum SO3/C3A ratio for mixtures with a low-level cement replacement with WA was between 0.4 and 0.5. Washed WA originating from grate combustion appeared to be most promising of the tested WAs in cement-based materials.