METHOD FOR DETERMINING FROST RESISTANCE OF CONSTRUCTION MATERIALS Russian patent published in 2000 - IPC

FIELD: construction industry. SUBSTANCE: method involves impregnating samples with water or sodium chloride solution; performing surface cyclic freezing and tawing of samples; providing visual estimation of frost resistance. Freezing is conducted for 5-10 min. Thawing of a portion of sample, for instance 0.1-0.2 of sample surface, is performed for 3-5 min. Freezing and thawing mode change is carried out at rate of 30-40 C per min. Samples are dipped into water or sodium chloride solution for 90-95% of their volume. Method may be used for testing construction materials, such as bricks, silicate or ceramic stone for frost resistance. EFFECT: reduced testing time, decreased labor consumption and increased reliability of test results.