Résumé:
In recent years, cementitious composite materials reinforced with vegetable fibers have gained increasing interest due to the need for sustainable building materials. Vegetable fibers are a hierarchical structure material that can be used as reinforcement in cement-based composites. This research work aims to investigate the use of vegetable fibers as reinforcement in cement-matrix composites for building applications. This research presents the development of construction bio-composites consisting of a cementitious matrix reinforced with hemp fibers and to optimize its behavior under compressive and 3-point bending tests. The hemp fibers were treated with different concentrations of soda solution and cut into different lengths before distributing them in mortar, to study the influence of these factors in mechanical tests. Then bio-composites of hemp/cement were elaborated with an experimental design using response surface methodology (RSM). The results obtained from mechanical tests after 28 days of curing were analyzed with the analysis of variance technic (ANOVA) to optimize the mechanical characteristics of the bio-composites developed. Next, these results have been converted into a mathematical model to understand the effect of changing factors on the mortar behavior using Design Expert software.