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High moisture in building materials has a negative influence on their physical and thermal insulating properties. When building materials incorporated in a structure exceed the maximum permissible moisture, the material could change its properties to such an extent that its next usage is unfeasible. In case of thermal insulating materials, it causes serious degradation of thermal insulating properties. During the development of advanced thermal insulation plasters, long-term laboratory experiments were performed using masonry construction fragments, which focused on the study of their moisture proportions. For this purpose a new non-destructive method of electrical impedance was used, which enables measurements on defined levels in a matrix of test samples. Results obtained by measurements made on the surface of the samples were compared with the results obtained by a capacitive hygrometer. It was concluded that these methods provided similar results. The least moisture sensitive was the mixture, which was applied on masonry pillar E. In comparison with used thermal insulation plasters commonly used today this plaster shows considerably lower value of mass moisture under laboratory conditions, 1.38%. This pillar also exhibited the most uniform course of conductance measured along its height. [ABSTRACT FROM AUTHOR]

A complex analysis of engineering properties of concrete containing natural zeolite as supplementary cementitious material in the blended Portland-cement based binder in an amount of up to 60% by mass is presented. The studied parameters include basic physical characteristics, mechanical and fracture–mechanics properties, durability characteristics, and hygric and thermal properties. Experimental results show that 20% zeolite content in the blended binder is the most suitable option. For this cement replacement level the compressive strength, bending strength, effective fracture toughness, effective toughness, and specific fracture energy are only slightly worse than for the reference Portland-cement concrete. The frost resistance, de-icing salt resistance, and chemical resistance to MgCl 2 , NH 4 Cl, Na 2 SO 4 , and HCl are improved. The hygrothermal performance of hardened mixes containing 20% natural zeolite, as assessed using the measured values of water absorption coefficient, water vapor diffusion coefficient, water vapor sorption isotherms, thermal conductivity, and specific heat capacity, is satisfactory. [ABSTRACT FROM AUTHOR]