On the Curing of Concrete for the Prestressed Concrete Works in Site

Abstract

For the purpose of getting same curing effect both on prestressed concrete products and their specimens, three kinds of tests were carried out.
All the tests were dome at the actual concreting works and classified as follows:
(1) Natural curing for post-tensioning bridge beam, in summer.
(2) Ditto, in winter.
(3) High temperature steam curing for pre-tensioning railway sleeper, in factory.
As the test results, the following facts were obtained.
(1) Keeping the specimen merely under the same cover for the product is not sufficient.
(2) Pretty good effects were observed when the specimens had been wrapped up with wet paper and put in a wooden box stuffed with air-insulating materials, then the box was placed under the same cover of the product.
(3) As air-insulating materials, waste sack cloth and chaffs were used, which are easily available on the spot.