 |
Since then, a number
of large non-reinforced concrete prisms 305 x 305 x 915-mm in size, incorporating
different percentages of supplementary cementing materials have been installed
at the above exposure site at almost yearly intervals. Also, a number
of reinforced-concrete prisms were installed at the site in 1991. As of
August 1995, there were more than 250 prisms at the exposure site, and
these prisms are being monitored yearly using visual examination and non-destructive
test method In 1986, 1987, 1994, and 1996 reports and papers were published
outlining the scope of the program and giving performance data on the
conditions of the prisms (1,2,3,4). This paper presents a comprehensive
account of the conditions of the test prisms, including the results of
the last inspection which was held in August 1999. Also included in the
CANMET program is a study on Alkali-Aggregate Reaction consisting of 12
concrete prisms (see Phase XIV) incorporating reactive and non-reactive
aggregates and various binder compositions to counteract these reactions.
The prisms can be seen in the center of the above picture. |
| The Canada Centre for Mineral and
Energy Technology (CANMET) has an ongoing program dealing with the long-term
performance of supplementary cementing materials in concrete. The supplementary
cementing materials being investigated include low- and high-calcium fly
ashes, pelletized and granulated blast-furnace slags, silica fume, rice-husk
ash, and metakaolin. |
In 1978, as part of this research
program, CANMET initiated a study to determine the performance of concrete
with and without some of the above supplementary cementing materials at
Treat Island, Maine, an outdoor marine exposure facility operated by the
U.S.Army Corps of Engineers, Vicksburg, Mississippi. |