The effect of doum palm fibers on the mechanical and thermal properties of gypsum mortar

Fatma Naiiri (1) , Lamis Allègue (1) , Mehdi Salem (2) , Redouane Zitoune (2) , Mondher Zidi (1)

1 LGM / ENIM - Laboratoire de Génie Mécanique [Monastir]
2 ICA - Institut Clément Ader

The main objective of this paper is the evaluation of the possibility of using a gypsum mortar reinforced with doum palm fibers as thermal insulators in building material. Several composite configurations with three sizes and five-weight ratios (from 0.5% to 2.5%) of doum palm fiber were prepared for mechanical and thermo-physical characterization. Generally, natural fibers are affected by the alkali environment of gypsum mortar. To overcome this problem, doum palm fibers were treated with a NaOH solution of 1% concentration to enhance their resistance against chemical degradation. Chemical treatment of fiber removes some hemicellulose and lignin and tends to make the fiber more homogenous, which enhances fiber–matrix interfacial properties. In addition, the mechanical properties of the specimens were tested after 7 days, 28 days and 1 year of curing in normal conditions. The obtained results show an improvement in the mechanical performance of composites reinforced with treated fibers. In fact, better results were obtained for gypsum mortar reinforced with treated reinforcement seive2 for the value of 1% of fibers. It was also noticed that NaOH treatment has an influence on the thermal conductivities. In fact, the use of treated doum palm fibers as reinforcement in gypsum mortar seems to be an alternative natural material to be used as a thermal insulator material.

Mots clés: thermo-physical test; Gypsum mortar; doum palm fiber; building material; alkali treatment; mechanical test

Domaines: Sciences de l'ingénieur [physics]; Génie civil; Matériaux

Fatma Naiiri, Lamis Allègue, Mehdi Salem, Redouane Zitoune, Mondher Zidi. The effect of doum palm fibers on the mechanical and thermal properties of gypsum mortar. Journal of Composite Materials, 2019, 53 (19), pp.2641-2659. ⟨10.1177/0021998319838319⟩. ⟨hal-02134405⟩