One of the authors, S. Rémond, would like to thank ADEME for their financial support. The authors also thank the Vicat Company that carried out the chemical and size grading analyses of the MSWI fly ash, and the Cylergie Company for interpreting the fly ash and cement paste XRD diagrams. The assistance of Paul Stutzman (BFRL/NIST) in performing the SEM analysis is greatly appreciated. S. Rémond would also like to thank the staff of BFRL for their hospitality during his six-month stay at NIST.