Microstructures of hardened mortars using eco-cements and sintered sewage sludge

Abstract

Strength development and microstructures were investigated for a hardened mortar using eco-cement manufactured by replacing a part of the raw materials with incineration ash of urban waste and a waste-derived aggregate of sintered sewage sludge. Back-scattered electron images and X-ray image maps showed that the porous zones of Ca(OH)2 usually observed at the interface between the normal Portland cement paste and aggregate did not form in mortars using the eco-cements. The hydration processes of eco-cements were discussed based on distribution maps of Cl, S, Mg, Na, K, Fe, Si, Al, Ca, and O.