chapter 3 rigid pavement - DOT On-Line Publications - Department ...

FBWA TECHNIC= ADVISORY T 5080.17
July 14, 1994
(b)
(cl
Precautions need to be taken when
using fly ash in concrete at lower
temperatures. It should also be
noted that fly ash can reduce early
strength development and,
therefore, should be monitored
closely.
Ground granulated blast furnace slag
specifications are contained in
AASHTO M 302.
A Ground granulated blast furnace
slag (GGBFS) is a cementitious
material and can be substituted for
cement on a 1:l basis by weight for
up to 50 percent of the cement in
the mix.
a For fresh concrete using GGBFS, the
air entrainment agent dosage may
need to be increased. The
workability and finishability
typically are improved but in mixes
having high cementitious material
content, mixes can be sticky and
difficult to finish. Bleeding may
be reduced and setting time may be
longer.
1 Ground granulated blast furnace
slag can reduce sulfate attack,
alkali-aggregate reactions, and
permeability. The rate of strength
gain is usually decreased and
sensitive to low temperature.
Microsilica specifications are contained
in AASHTO M 307. Microsilica can be
used as an admixture or as a replacement
for an equivalent amount of cement to
produce high strength concrete.
Microsilica will reduce permeability and
help reduce alkali-aggregate reactions.
3.10.10