Publications Internationales
Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13
Browse
4 results
Search Results
Item Quasi-static mechanical characterization and fatigue of a composite laminates(2014) Belkacemi, C.; Bezzazi, B.This present work focuses on the quasi- static mechanical characterization and or fatigue of a composite materials (laminate) jute/polyester manufactured under vacuum and with stacking sequences of 0/ 90. The obtained results of tensile tests on the laminate, showed a similar behavior on two levels: a linear portion up to 20 MPa and a nonlinear portion to rupture at 47 MPa σ max , followed by elongation of 2.08 % with a break elongation up to 2.50 %. Also, it was noted that increasing the temperature of the samples (5-6 ° C ) when the fatigue test remains in ISO 13003 , which requires a temperature increase of less than 10 ° C. the results of fatigue test showed also that with a loading of 50% of the maximum load reached more than one million cycle, the more load is increasing the cycle numbers of decreasesItem Study of the green composite Jute/Epoxy(2014) Mir, A.; Aribi, C.; Bezzazi, B.Work presented is interested in the characterization of the quasistatic mechanical properties and in fatigue of a composite laminated in jute/epoxy. The natural fibers offer promising prospects thanks to their interesting specific properties, because of their low density, but also with their bio-deterioration. Several scientific studies highlighted the good mechanical resistance of the vegetable fiber composites reinforced, even after several recycling. Because of the environmental standards that become increasingly severe, one attends the emergence of eco-materials at the base of natural fibers such as flax, bamboo, hemp, sisal, jute. The fatigue tests on elementary vegetable fibers show an increase of about 60% of the rigidity of elementary fibers of hemp subjected to cyclic loadings. In this study, the test-tubes manufactured by the method infusion have sequences of stacking of 0/90° and ± 45° for the shearing and tensile tests. The quasistatic tests reveal a variability of the mechanical properties of about 8%. The tensile fatigue tests were carried out for levels of constraints equivalent to half of the ultimate values of the composite. Once the fatigue tests carried out for well-defined values of cycles, a series of static tests of traction type highlights the influence of the number of cycles on the quasi-static mechanical behavior of the laminate jute/epoxyItem Study of mechanical and thermomechanical properties of jute/epoxy composite laminate(2010) Mir, A.; Zitoune, R.; Collombet, F.; Bezzazi, B.This article presents the development and the characterization of composite material (laminate) containing natural jute fiber reinforcement. Thermal characterization of jute fiber reinforcement shows the influence of the temperature on the mechanical behavior of fiber. At 180 C the jute fabric loses 50% of its mechanical characteristics. The laminate obtained by a process known as infusion is polymerized at a temperature lower than that which affects the mechanical properties of dry fabric. The digital image correlation carried out on laminated jute/epoxy (warp and weft direction) under tensile test shows the presence of a considerable gradient of deformation. This gradient is explained by the variability related to the local voluminal change of jute fibers of one place to the other and the nature of the weaving of the jute fiber. The three-point bending tests show a significant dispersion of rupture stress. The thermomechanical tests carried out on samples in the two principal directions, show that the thermal coefficient of expansion in warp direction is 48% larger compared to the weft direction. The thermogravimetric test shows that this laminate absorbs up to 4% water mass after 8 h in a climatic chamber with 70% moisture contentItem Fatigue behaviour of the laminates jute/epoxy(2013) Mir, A.; Aribi, C.; Bezzazi, B.Work presented is interested in the characterization of the quasistatic mechanical properties and in fatigue of a composite laminated in jute/epoxy. The natural fibres offer promising prospects thanks to their interesting specific properties, because of their low density, but also with their bio deterioration. Several scientific studies highlighted the good mechanical resistance of the vegetable fibre composites reinforced, even after several recycling. Because of the environmental standards which become increasingly severe, one attends the emergence of eco-materials at the base of natural fibres such as flax, bamboo, hemp, sisal, jute. The fatigue tests on elementary vegetable fibres show an increase of about 60% of the rigidity of elementary fibres of hemp subjected to cyclic loadings. In this study, the test-tubes manufactured by the method infusion have sequences of stacking of 0/90° and ± 45° for the shearing and tensile tests. The quasistatic tests reveal a variability of the mechanical properties of about 8%. The tensile fatigue tests were carried out for levels of constraints equivalent to half of the ultimate values of the composite. Once the fatigue tests carried out for well defined values of cycles, a series of static tests of traction type highlights the influence of the number of cycles on the quasi static mechanical behavior of the laminate jute/epoxy
