Abstract
The present paper extends previous findings already published where the relationships among total porosity, bulk density, compressive strength, and thermal conductivity were analysed. The paper brings more accuracy into some original mathematical relationships and takes into account two additional physical properties (pore volume and the median pore radius). It has been found that the relationships between physical properties and a dose of any admixture added to brick clay could be better described using a quadratic function. The relationships between pairs of physical characteristics can be described by three types of mathematical function (linear, exponential, and power). The amount of admixture used, the firing temperature, and type of clay affect the value of the coefficients but not the type of functions.