EFFECT OF TEMPERATURE ON THE CURING OF MEDIUM-CEMENT
REFRACTORY CONCRETE WITH A COMPOSITE DEFLOCCULANT
and I. Demidova-Buizinene
Translated from Novye Ogneupory, No. 11, pp. 50 – 54, November, 2011.
Original article April 22, 2011.
Results are presented from studies of the properties of medium-cement refractory concrete with a composite
deflocculant (the ratio of sodium tripolyphosphate to polycarboxylate ether Castament FS-20 in the
deflocculant was 2/1). The properties are examined as a function of the curing temperature (+10, +20, and
+30°C) and the choice of cement (Gorkal 40, Gorkal 70). The effect of curing temperature on the rheology of
the paste and the strength of the concrete is also discussed.
Keywords: medium-cement refractory concrete, composite deflocculant, microsilica, mullite filler, curing
temperature, viscosity, physico-mechanical properties.
A composite composed of two deflocculants (sodium
tripolyphosphate and polycarboxylate ether Castament
FS-20) can be used to control hydration rate and structure
formation in medium-cement refractory concrete during the
curing process . Studies of the exothermic reaction tem-
perature in concrete have shown that sodium tripoly-
phosphate helps increase hydration rate and that Castament
FS-20 decreases it. Studies of the effect of different
deflocculants on the hydration of high-alumina cements
(Gorkal 70, Gorkal 70F, Gorkal 80) have shown that sodium
tripolyphosphate, Castament FS-20, and the composite
deflocculant all retard the hydration of the cement, regardless
of the type of cement that is used . A comparative analysis
of the physico-mechanical properties of medium-cement
heat-resistant mullite concrete showed that the type of ce
ment notwithstanding, the use of a composite deflocculant
makes it possible to obtain concrete with improved strength
characteristics (ultimate compressive strength of more than
150 MPa after heat treatment at 800 – 1200°C). When ce
ments Gorkal 70F and Gorkal 80 are used, the use of a com
posite deflocculant produces concrete with more stable val
ues for shrinkage at 800 – 1200°C.
However, it has also been observed that the quality of
modern refractories made with deflocculating additives de
pends to a large extent on the temperature conditions during
the production and curing of the concrete [3 – 5]. This de-
pendence exists because the ambient temperature affects the
rate at which the strength of the concrete increases. A study
of the effect of ambient temperature  on the durability of a
specimen of a low-cement concrete with Castament FS-10
showed that after 30 min the dispersion index of the speci-
men prepared at 5°C was roughly 20% lower than the index
of the specimen prepared at 35°C. The EXO-maximum (the
maximum of the exothermic reaction with respect to time
and temperature) of the specimen that set at 5°C was re
corded after 160 h, while the EXO-maximum of the speci
men that set at 35°C was recorded after 30 h of curing. In ad
dition to examining the durability parameters of concrete as a
function of the flocculant which is used, the study  investi
gated the ultimate compressive strength of low-cement con
crete after curing for 1 day at 5, 20, and 35°C. It is estab
lished that the lower the temperature at which specimens are
cured, the slower the rate of increase in the strength of the
concrete. Specimen strength was 0.1 – 4.0 MPa for a curing
temperature of 5°C, 4 – 32 MPa for a curing temperature of
20°C, and 15 – 40 MPa for a curing temperature of 35°C.
The exact strength value within these respective ranges de
pended on the type of deflocculant that was used.
The goal of our investigation was to examine how the
properties of medium-cement concrete with a composite
deflocculant are affected by the temperatures at which the
concrete is made and cured.
Refractories and Industrial Ceramics Vol. 52, No. 6, March, 2012
1083-4877/12/05206-0414 © 2012 Springer Science+Business Media, Inc.
From materials of the International Conference of Refractory
Specialists and Metallurgists (March 31 – April 1, 2011, Moscow).
Vilnius Technical University, Vilnius, Lithuania.