High temperature concrete
- View SourceI am pouring a heat resistant concrete for the boiler containment
housing. The concrete is a 1-2-3 mix of cement, sand and vermiculite. I
have some high temp ceramic fiber insulation I am going to line the
concrete box with as well. The book at the library indicates this type
of concrete will withstand temps of 3000 degrees F. It is a chalky mix
and will not tolerate large spans and will not support much weight.
The first batch I poured was in a vertical form. The form was removed
after 5 days. This batch did not settle well into the form and did not
dry fast enough inside the form. A large crack made this piece unusable.
It was very light weight and I could easily lift a 3'x3' piece 2" thick.
I poured the next batch horizontally. I will leave these in the forms a
full week before removal. If these do not work I will try substituteing
perlite or cutting back on the vermiculate, as the strength of the
concrete is directly related to the strength of the aggriate.