Mechanical, hygric and thermal properties of building stones

摘要

Basic physical properties, pore distribution, mechanical, hygric, and thermal properties of several types of building stones which were used in historical buildings on the Czech territory in medieval times, namely several types of sandstone and argillite, are investigated. Bulk density, matrix density and open porosity are measured using the water vacuum saturation method, pore distribution by mercury porosimetry, compressive and bending strength by a hydraulic testing device. Apparent moisture diffusivity is determined by utilizing the results of water sorptivity measurements, the dependence of moisture diffusivity on moisture content is obtained by measuring moisture profiles using a capacitance technique and subsequent solution of the inverse problem of moisture diffusion. Water vapor diffusion permeability is measured by the cup method, sorption isotherms are determined by the desiccator method. Thermal conductivity and specific heat capacity are measured by an impulse technique in the moisture range from the dry state to full water saturation.