Effects of the Incorporation of Municipal Solid Waste Incineration Fly Ash in Cement Pastes and Mortars. Part 1: Experimental Study.
Effects of the Incorporation of Municipal Solid Waste
Incineration Fly Ash in Cement Pastes and Mortars. Part
1: Experimental Study.
(1373 K)
Remond, S.; Pimienta, P.; Bentz, D. P.
Cement and Concrete Research, Vol. 32, No. 2, 303-311,
2002.
Keywords:
solid waste; fly ash; cement paste; mortar; cements;
hydration; microstructure; waste materials
Abstract:
This work falls within the scope of a general problem
regarding the assessment of concretes manufactured from
waste materials. The main objective is to study the
long-term evolution of these materials during the
leaching process, using the cellular automata based
hydration model developed at the National Institute of
Standards and Technology. The work is based on the
analysis of mortars and cement pastes containing
experimental waste: Municipal Solid Waste Incineration
fly ash (MSWI fly ash). The study therefore aims to
develop a methodology for assessing concretes
manufactured from waste, and not to study a process or a
formulation enabling the incorporation of the waste in
concrete. The physical, chemical, and mineralogical
characteristics of MSWI fly ash were first analyzed to
introduce them into the model. A simplified quantitative
mineralogical composition of the ash was proposed. The
performance characteristics for mortars containing ash
were then studied. This study showed that the soluble
fraction of the ash, in particular chloride, had a
significant influence on the properties of mortars. The
hydration products that form in cement pastes in the
presence of ash were then examined so as to include the
ash/cement interactions in the hydration model. In
particular, the ash chlorides modify the hydration
reactions of the cement's calcium aluminates.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899