ACCELERATION OF THE PORTLANDCEMENT MORTAR DURABILITY TEST

Abstract

The paper offers a discussion of results obtained during a joint test of the resistance of cement mortar samples to frost and sulphate corrosion. It has been found that with the cyclic freezing of mortar samples saturated in the 5% Na₂SO₄ solution and their subsequent thawing in the solution it is possible to accelerate twice the begining of their deterioration. A new method of accelerated determination of the cement product durability has been worked out. The following recommendations should be considered: 40 × 40 × 160 mm samples should be made of cement and standard CEN sand with their mass ratio C / S = 1 : 4 and water and cement ratio W / C = 0.6. Freezing should be performed during 7 ±1 h at -18 ±2 °C, and the samples should be kept soaked in the 5% Na₂SO₄ solution at room temperature. The duration of one cycle is 24 h, and the duration of the whole test depends on the type of cement and may take 3 to 6 months.

DOI: http://dx.doi.org/10.5755/j01.ct.59.1.1525