Alkali-Silica Reaction and High Performance Concrete.
Alkali-Silica Reaction and High Performance Concrete.
(1348 K)
Ferraris, C. F.
NISTIR 5742; 24 p. August 1995.
Available from:
National Technical Information Service
Order number: PB96-131587
Keywords:
building technology; alkali-silica reaction; high
performance concrete; concretes; standard testing
Abstract:
Damage due to alkali-silica reaction (ASR) in concrete
is a phenomenon that was first recognized in the U.S.
since 1940 and has since been observed in many
countries. Despite numerous studies published, the
mechanism is not yet clearly understood. Nevertheless,
the three major factors in concrete have been
identified, i.e., the alkalies contained in the pore
solution, reactive amorphous or poorly crystallized
silica present in certain aggregates, and water. In
this study, we attempted to address the question: is
high-performance concrete (HPC) susceptible to ASR?
Researchers have not reached an agreement on this matter
because factors other than the three major ones (pore
solution alkalinity, aggregate morphology and water
presence) play a significant role in the occurrence of
ASR; these factors include aggregate gradation, w/c and
compressive strength. It was found that air content is
the most important variable (other than the three majors
factors cited above) that increase expansion of
concretes affected by ASR. This study indicates that
even HPC should be susceptible to ASR if reactive
aggregates are used.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899