Title:
Adiabatic Temperature Rise in Concrete With and Without GGBFS
Author(s):
C. T. Tam, Y. H. Loo, and K. F. Choong
Publication:
Symposium Paper
Volume:
149
Issue:
Appears on pages(s):
649-664
Keywords:
adiabatic conditions; binders (material); blast furnace slag; heat of hydration; high-performance; mix proportioning; temperature rise; Materials Research
DOI:
10.14359/4116
Date:
10/1/1994
Abstract:
The control of differential thermal stress or strain due to heat of hydration in a thick concrete section can be a requirement for a high-performance concrete. An investigation was carried out to study the use of ground granulated blast furnace slag (GGBFS) as partial replacement of cement to reduce the adiabatic temperature rise of concrete. By testing concrete mixes instead of cement pastes, this study includes the effects of not only the cement but also the presence of aggregates in their proportions and directly relates the mix to the job. A computer-controlled cell is designed to measure the adiabatic temperature rise in concrete with initial concrete temperature at 20, 30, or 40 C. Slag replacement up to 70 percent by mass of total cementitious binder content was studied. Other parameters studied include water-binder ratio ranging from 0.40 to 0.60, fineness from 300 to 400 kg/m 2, and binder content from 250 to 350 kg/m 3 of concrete. The results of the adiabatic temperature rise in concrete show that an increase in slag replacement reduces the temperature rise. The effect of higher fineness or higher total cementitious binder content leads to higher temperature rise. However, the influence of placing temperature on the temperature rise indicates a lower rise at higher placing temperature. It is also noted that at higher placing temperature, slag replacement greater than 55 percent by mass tends to reduce temperature rise to a greater extent than at lower replacement levels. The development of the heat of hydration with time of the concrete mixes under adiabatic condition is expressed in equation form.