This paper presents an experimental study of the influence of the addition of palm nut fiber on the mechanical strength of cement mortar. Cement mortar specimens reinforced with naturals palm nut fibers have been developed containing between 0 and 3.5% volume fraction fibers. Compression test and flexural test (3-point bending test) are performed on the different samples. It is found from the flexural test that the flexural strength of the mortar reinforced with palm nuts increases slightly regardless of the maturation time of the sample. Conversely, compression tests show a gradual decrease in mechanical strength with the addition of fibers.

Composite materials based on natural fibers are increasing in demand in various sectors of industry because of their interesting specific properties. This work is a contribution to the valorization, of plant fibers from agricultural plantations in Cameroon, in fiber cement mortar (FCM). This paper studies the influence of the addition of oil palm mesocarp fiber (OPMF) on the physical (water absorption, density and compactness) and mechanical (compressive strength and flexural strength) properties of cement mortars. The fibers used in this paper are extracted from oil palm mesocarp (palm kernel pulp) by a mechanical and manual process. Cement mortar specimens were then made with different proportions of fibers: 0% (reference mortar), 1%, 2%, 3% and 3.5% fibers. Physical and mechanical tests are then carried out on our specimens. Regardless of the duration of immersion in water, the results show that the water absorption rate increases with a greater amount of fiber in the FCM specimens. On the other hand, an inverse effect is observed on density, which decreases from 2277.5 (samples with 0% fiber) to 942.1 kg/m3 (samples with 3.5% fiber) for apparent density and from 2641.2 to 1945.7 kg/m3 for absolute density. On the mechanical properties, there is a steady decrease in compressive strength from 42.47 (for the reference mortar at 0% fiber) to 31.1 MPa (for the sample at 3.5% fiber). In bending, there is first an increase and then a decrease in strength with the amount of fibers. The maximum flexural strength is obtained for a 2% fiber composition. The FCM has a better strength/density ratio. Finally, the addition of OPMF, in small proportion in the cement mortar, allows a lightening of the structure, but induces a small decrease in mechanical resistance. Our FCM can be used in the manufacture of cinderblocks or as internal wall roughcoating mortar.

soumission à Episciences This paper is dedicated to the implementation of a law of mechanical behavior in the finite element software Cast3M using an open source code generator named Mfront. To do so, an elastoplastic behaviour model has been chosen from existing laws in the literature. Following an implicit discretization, a hardware library corresponding to the isotropic and kinematic strain-hardening model is generated using Mfront. The UMAT computer interface is used to build the library in Cast3M. A validation of the approach has been carried out by comparing the numerical results obtained with the generated hardware library and the equivalent pre-existing library in Cast3M. Simulations in the case of a tensile bar and a perforated plate show almost identical results Ce papier est dédié à l’implantation d’une loi de comportement mécanique dans le logiciel éléments finis Cast3M à l’aide d’un générateur de code open source nommé Mfront. Pour ce faire, un modèle de comportement élasto-plastique a été choisi à partir des lois existantes dans la littérature. Suivant une discrétisation implicite, une bibliothèque matérielle correspondant au modèle de CHABOCHE à écrouissage isotrope et cinématique non linéaire est générée grâce à Mfront. L’interface informatique UMAT est utilisée pour construire la bibliothèque dans Cast3M. Une validation de l’approche a été menée en comparant les résultats numériques obtenus entre la bibliothèque matérielle générée et la bibliothèque équivalente préexistante dans Cast3M. Les simulations dans le cas d’une barre en traction et une plaque trouée montrent des résultats quasi identiques

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