Compressive Strength, Thermal Conductivity, Vapor Permeability and Specific Heat of Hemp-Lime Composites Varying in Density for Wall, Roof and Floor Applications
Michał Gołębiewski, Barbara Pietruszka, Wojciech Piątkiewicz, M. Kubiś, Олена Олексієнко
Abstract
Hemp-lime composites, characterized by pro-environmental features, offer an interesting alternative to traditional building materials. The properties of these materials depend on many factors, leading to uncertainty regarding the results obtained when designing building envelopes. Volumetric density-a key factor-depends on the manufacturing technique adopted, among other things, and can be controlled. In this study, materials for use in partitions constituting the building envelope were produced at various densities through varying degrees of compression and subjected to tests to determine their compressive strength, thermal conductivity and water vapor permeability. The values obtained were in the wide ranges of 0.05-1.50 MPa, 0.0671-0.1339 W/(m∙K) and 3.61-10.10, respectively. Furthermore, the specific heat was determined to be 1178-1260 at 60 °C and 773-863 J/(kg∙K) at 30 °C. The test results clearly indicate the dependence of the tested properties on the mixture composition, volumetric density and composite structure. The results of this study demonstrate the suitability of the considered material for construction applications and the significant variations in its properties. Understanding the relationships between the properties of different composites and their degree of compaction can facilitate the design process and help in modeling the mechanical and thermal behaviors of partitions and entire buildings.