A new approach in the field of sustainable building materials is based on the use of renewable raw materials instead of non-renewable ones. A great potential for the use of fast renewable raw material has a group of plants that are the source of fibers and non-fibrous components. The use of plant fibers and/or particles as fillers into building material with reinforcement function of composite is motivated by the need to develop environmentally friendly products in accordance with principles of sustainable development in the building industry. Our research interest is concentrated on the possibilities of using technical hemp especially hemp waste – hurds/shives like non-fibrous fraction originating from the production of hemp fibers into lightweight composite.
This paper gives an overview of the results of an experimental study of the parameters affecting the physical and mechanical properties of hemp composite based on MgO-cement as a binder. The influence of parameters such as hemp proportion (20-60 vol. %) and mean particle length of anisometric hemp hurds slices (2,33 – 7,42 mm; 40 vol. % hemp hurds) on some physical (density, thermal conductivity, water absorption) and mechanical properties (compressive strength) of composite after different curing time is studied. Composites prepared by varying the proportion of hemp hurds in the mixture reached increase in values of compressive strengths in dependence on organic filler content and hardening time. Strength characteristics of hardened composites depend not only on the proportion of hemp hurds in the mixture, but also on the mean lenght of hemp particles. Effect of mean length of hemp hurds slices on the above mentioned characteristics of composites was confirmed. Physical properties of hardened composites are improved when mean hemp particle length decreases what is related to the creation of more dense structure for composite with particle dimensions smaller.
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