Elaboration and characterization of a bio-composite destined for construction.

Abstract

The composite materials industry evolves and grows continuously by introducing new materials and technologies. As an alternative for mineral materials, materials of natural origin (especially vegetable) started to be used. Due to their desirable characteristics such as low environmental impact, low cost, biodegradability, low density and good mechanical properties, the vegetable fibers have been extensively used as reinforcement in cement-based composite. Among the vegetable fibers family, date palm fibers (DPF) generated from the annual crop taking of date palm trees represent a considerable amount of vegetable fibers which normally considered as a waste or it is used for applications of daily life in low values of the total products. Date palm mesh fibers (DPMF) is a type that belong to these fibers, it is a cross mat of single fibers surrounding the stem of the date palm tree. The valorization of the DPMF is a major step toward the production of green lightweight cement-based materials and reducing the cost of materials destined for construction sector. The present thesis exposes an experimental investigation on the use of DPMF as reinforcement for cementitious materials. For this purpose, the influence of the DPMF’s inclusion with multiple fractions on the fresh properties of a cement mortar was studied. Furthermore, the mechanical performance of cement mortar composites has been examined through investigating the compressive, flexural and fracture behaviors. The results obtained show that the fresh properties of the reinforced mortar composites were not influenced after adopting such a mixing process in which the DPMF were introduced in wet state. The selected physical and mechanical properties of the cement-based mortar composites showed a decrease with the gradually increase of fibers content. Nevertheless, the inclusion of DPMF improves the post-peak behavior, the ductility and delays the failure of cementitious composites compared with plain mortar specimens. Also this study has shown an interesting fracture properties obtained for low content of DPMF ( 2% by volume). Previous research works reported a similar fracture toughness value.