Frost resistance and pore size distribution in bricks

Correlation between frost resistance, porosity and pore size distribution was examined. Different test methods were used to evaluate the frost resistance. Porosity and pore size distribution were examined in mercury intrusion porosimeter (MIP). Scanning electron microscopy gave a visual view of the pore geometry, pore size and porosity. A linear correlation was found between frost resistance and the inverse value of the intruded pore volume. A linear correlation was also found between frost resistance and percentage of pores with diameter bigger than 3 μm. The test results were analysed using statistical methods. From the MIP-test a frost resistance number can be calculated which indicates the frost resistance of the brick.