The growing demand in the use of composite materials necessitates a better understanding ofits behavior related to many conditions of loading and service, as well as under several waysof connections involved in mechanisms of structural projects. Within these project conditionsare highlighted the presence of geometrical discontinuities in the area of cross andlongitudinal sections of structural elements and environmental conditions of work like UVradiation, moisture, heat, leading to a decrease in final mechanical response of the material. Inthis sense, this thesis aims to develop studies detailed (experimental and semi-empiricalmodels) the effects caused by the presence of geometric discontinuity, more specifically, acentral hole in the longitudinal section (with reduced cross section) and the influence ofaccelerated environmental aging on the mechanical properties and fracture mechanism ofFGRP composite laminates under the action of uniaxial tensile loads. Studies onmorphological behavior and structural degradation of composite laminates are performed bymacroscopic and microscopic analysis of affected surfaces, in addition to evaluation by theMeasurement technique for mass variation (TMVM). The accelerated environmental agingconditions are simulated by aging chamber. To study the simultaneous influence ofaging/geometric discontinuity in the mechanical properties of composite laminates, a semiempiricalmodel is proposed and called IE/FCPM Model. For the stress concentration due tothe central hole, an analisys by failures criteria were performed by Average-Stress Criterion(ASC) and Point-Stress Criterion (PSC). Two polymeric composite laminates, manufacturedindustrially were studied: the first is only reinforced by short mats of fiberglass-E (LM) andthe second where the reinforced by glass fiber/E comes in the form of bidirectional fabric(LT). In the conception configurations of laminates the anisotropy is crucial to the finalmechanical response of the same. Finally, a comparative study of all parameters wasperformed for a better understanding of the results. How conclusive study, the characteristicsof the final fracture of the laminate under all conditions that they were subjected, wereanalyzed. These analyzes were made at the macroscopic level (scanner) microscope (opticaland scanning electron). At the end of the analyzes, it was observed that the degradationprocess occurs similarly for each composite researched, however, the LM compositecompared to composite LT (configurations LT 0/90º and LT ±45º) proved to be moresusceptible to loss of mechanical properties in both regarding with the central hole as well toaccelerated environmental aging
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