TESTING HEMP HURDS COMPOSITES WITH ALTERNATIVE BINDER

Composites based on natural fibres as organic filler are studied for several years because traditional building materials such as concrete are increasingly being replaced by advanced composite materials (fibre reinforced cement). The current trend in the construction industry is the effort to achieve sustainable development using rapidly renewable material resources instead of limited raw materials as well as using alternative materials. The need for development of promising and environmentally friendly materials is related to the industrial interest in the use of natural plant fibres as reinforcement into lightweight composites. The attention is given to hemp fibres as a substitute for synthetic fibers in lightweight composites due to their unique mechanical, thermal insulation, acoustic and antiseptic properties. Optimizing the adhesion of hemp plant fibre to the inorganic matrix in the composite is related to the modification of hemp fibers and/or the appropriate option and treatment of binder. In this paper, the attention is given to the study properties of composite based on hemp hurds (the woody part of hemp plant) as filler and alternative binder (MgO-cement). The hemp as a building composite component is rapidly renewable, carbon-negative, non-toxic, mildew-resistant and pest-free. Cement based on MgO seems to be a suitable binding agent for composites based on hemp hurds. Experimental work is focused on the study of thermal treatment of natural raw magnesite material for its subsequent use as an alternative binder component for lightweight composites and variation of composite mixtures based on hemp hurds and alternative binder focused on the MgO and SiO₂ component (silica sand and silica fume in variation). The evaluation of the physical and mechanical properties of hemp hurds composites with alternative binder is given. The results have shown that by incorporating hemp hurds into a magnesium oxide cement matrix it is possible to prepare materials with suitable thermal insulating properties usable in non-load-bearing structures.

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[1] Sedan D., Pagnoux S., Smith A., Chotard T. Mechanical properties of hemp fibre reinforced cement: Influence of the fibre/matrix interaction. Journal of the European Ceramic Society. Vol. 28. pp. 183-192, 2008.

[2] Cigasova J., Stevulova N., Junak J. Influence of binder nature on properties of lightweight composites based on hemp hurds. International Journal of Modern Manufacturing Technologies. Vol. 5. pp. 27-31, 2013.

[3] Valadez-Gonzalez A., Cervantes J.M., Olayo R., Herrera Franco P.J. Effect of fibres surface treatment on the fibres-matrix bond strength of natural fibres reinforced composites. Composites: Part B. Vol. 30. pp. 309-320, 1999.

[4] Stevulova N., Schwarzova I. Changes in the properties of composites caused by chemical treatment of hemp hurds. International Journal of Chemical, Biomolecular, Metallurgical, Materials Science and Engineering. Vol. 8. pp. 363-367, 2014.

[5] Kidalova L., Terpakova E., Stevulova N., Sicakova A. Application of hemp in preparation of building materials. Czasopismo Techniczne. Vol. 108. No. 8, pp. 107-112, 2011.

[6] Kidalova L., Terpakova E., Stevulova N. MgO cement as suitable conventional binder’s replacement in hemp concrete. Pollack Periodica. Vol. 6. pp. 107-112, 2011.

[7] Čigášová J., Števulová N., Sičáková A. New biocomposites based on hemp hurds. Journal of Civil Engineering, Environment and Architecture. Vol. 32. No. 62, pp. 75-81, 2015.

[8] Kidalova L., Stevulova N., Terpakova E., Sicakova A. Utilization of alternative materials in lightweight composites. Journal of Cleaner Production. Vol. 34, pp. 116-119, 2012.

[9] Stevulova N., Schwarzova I., Estokova A., Holub M. MgO-based cement as an inorganic binder for hemp hurds composites. Cheminé Technologija. Vol. 67, pp. 24-29, 2016.

[10] Kidalova, L. Determination of selected characteristics in hemp concrete. In: Young Scientist: 3rd PhD. Student Conference of Civil Engineering and Architecture. Košice. Slovakia. pp. 1-6, 2011.

[11] Bydzovsky, J. Utilization of rapidly renewable raw materials in building materials. In: Proceedings of the 12th International Scientific Conference. Brno Technical University, Brno, Czech Republic. pp. 43-46, 2009.

[12] STN EN 206-1/A1: 2009 Concrete. Part 1 Specification, performance, production and conformity.

[13] STN EN 12390-7: 2011 Testing hardened concrete. Part 7 Density of hardened concrete.

[14] STN EN 12087/A1: 2007 Thermal insulating products for building applications.

[15] Stevulova N., Cigasova N., Purcz P., Schwarzova I., Kacik F., Geffert A. Water absorption behavior of hemp hurds composites. Materials. Vol. 8, pp. 2243-2257, 2015.

[16] Estokova A., Kovalcikova M., Luptakova A., Prascakova M. Testing silica fume-based concrete composites under chemical and microbiological sulfate attacks. Materials. Vol. 9, pp. 1-15, 2016.