2.5. Heat evolution of concrete
The heat evolution of concrete containing ground bagasse ash under semi-adiabatic
conditions was investigated. Ground bagasse ash (BA) was used to replace
the Type I Portland cement at 10, 20, and 30wt% of binder. The mix proportion of
the concrete used in this investigation was the same as that for the study of the
compressive strength and water permeability. Concrete samples were cast in
450 mm cube molds lined with an insulator made of 50 mm expanded polystyrene
on each side. The heat evolution, in terms of temperature rise, was measured by
inserting a thermocouple into the center of the concrete specimen for a period of
168 h (7 days). The temperature rise of the concrete containing ground bagasse
ash was compared with that of the control concrete. Fig. 2 shows a schematic representation
of the concrete heat evolution test.
Note that the heat evolution of the concrete containing original bagasse ash was
not examined since its compressive strength was much lower than that of the control
concrete. This was because the particles of the original bagasse ash were large
compared with those of Portland cement [9]. Thus, original bagasse ash is not suitable
for use as a replacement for Portland cement.