This paper is devoted to investigate the effect of high temperatures on the behavior
and compression resistance of rectangular high-resistance concrete samples.
In this study, rectangular samples with dimensions of (15X15X15 cm) have been
made and
after 28 days they have been burned in a special oven, then cooled down in the
air.
The exposition of high-resistance concrete samples which made of local sand and
aggregate and use silica fumeoiiuk to high temperatures has led to a reduction and lose in
the compressive resistance of this samples.
When the temperature was 350 c, the reduction in the compressive resistance was
about 13%, and at the temperature of 450c, the reduction was about 36%, and at the
temperature of 850c, the reduction was about 72%.
Therefore, we have to take this reduction of compressive resistance in the concrete
elements seriously when they exposed to fire, so we can take the right decisions about
rehabilitation or conservation or replacement of this elements.
