Behaviour of ASTM type V cement hydrated in the presence of sulfonated melamine formaldehyde

ASTM Types I and V Portland cements were hydrated up to 28 days in the presence of 0.3%and 0.6% sulfonated melamine formaldehyde (SMF), at a water/cement ratio of 0.35.Hydration was studied by conduction calorimetric and thermogravimetric analyses. Theamount of Ca(0 Hh produced, compressive strength and porosity l!'ere determined after 1, 3,7 and 28 days of curing. The compressive strengths of all samples increased with the age ofcuring. In the period studied the values decreased in the order: Type I cement(reference) = Type I cement + SMF> Type V cement (reference) ~ Type V cement + SMF.The superplasticizer addition retarded the development of heat in the cements, but moreseverely in Type V cements. Porosities were generally higher for samples with 100vercompressive strengths. In the presence of 0.6% SMF, the early lOll' strengths in Type Vcement mixtures could be attributed to lower degrees of hvdration. At later ages, themicrostructure rather than the degree of hydration determined the strength development.However, incorporation of 0.3%SMF in Type V cement did not affect its strength development.Des ciments Portland de types ASTM I et V ont \ue9t\ue9 hydrat\ue9s pendant une p\ue9riode allant jusqu?\ue0 28 jours en pr\ue9sence d?ald\ue9hyde formique de m\ue9lamine sulfon\ue9 (SMF) \ue0 raison de 0,3 % et de 0,6 %, \ue0 un rapport eau/ciment de 0.35. L?hydratation a \ue9t\ue9 \ue9tudi\ue9e au moyen d?analyses calorim\ue9triques \ue0 conduction et thermogravim\ue9triques. La quantit\ue9 de Ca(OH)2 produite, la r\ue9sistance \ue0 la compression et la porosit\ue9 ont \ue9t\ue9 d\ue9termin\ue9es apr\ue8s des temps de cure de 1, de 3, de 7 et de 28 jours. La r\ue9sistance \ue0 la compression de tous les \ue9chantillons augmentait avec l?\ue2ge de la cure. Au cours de la p\ue9riode couverte par l?\ue9tude, les valeurs d\ue9croissaient selon l?ordre suivant : ciment de type I (contr\uf4le) = ciment de type I + SMF> ciment de type V (contr\uf4le) = ciment de type V + SMF. L?ajout de superplastifiant a retard\ue9 le d\ue9veloppement de la chaleur dans les ciments, mais de fa\ue7on plus marqu\ue9e dans ceux du type V. Les porosit\ue9s \ue9taient g\ue9n\ue9ralement plus \ue9lev\ue9es dans le cas des \ue9chantillons aux valeurs de r\ue9sistance \ue0 la compression plus faibles. En pr\ue9sence de SMF \ue0 0,6 %, les r\ue9sistances faibles aux jeunes \ue2ges dans les m\ue9langes de ciment de type V pourraient \ueatre attribuables aux degr\ue9s d?hydratation plus faibles. Aux \ue2ges plus avanc\ue9s, c?est la microstructure plut\uf4t que le degr\ue9 d?hydratation qui d\ue9terminait le d\ue9veloppement de la r\ue9sistance. Toutefois, l?incorporation de SMF \ue0 0,3 % dans le ciment de type V n?a pas nuit au d\ue9veloppement de sa r\ue9sistance.Peer reviewed: YesNRC publication: Ye