An interval-based method is presented to evaluate the uncertainty in computed mechanical properties and failure assessment of composite unidirectional (UD) laminates. The was applied two laminates: a carbon/epoxy glass/epoxy. UD lamina were derived using simplified micromechanical equations. level ±5% assumed for input constituents. global minimum maximum values an interval branch-and-bound alg...

In this work, the time-dependent mechanical behavior of a short carbon fiber-reinforced PEEK is investigated at temperatures near and above glass transition temperature for stresses below damage threshold. An experimental procedure including creep/recovery tests dynamic was carried out by varying stress levels, fiber orientation. The shown to be linear viscoelastic Effect orientation on elastic...

a new model is proposed in this research to calculate the longitudinal strengthof unidirectional e-glass reinforced polymer composites exposed to sulfuricacid environment, using a micromechanics model. in the proposed method,it is assumed that the residual strength of the degraded composites under acidic environment can be calculated by knowing the degraded strength properties of the constituen...

Important properties of fiber-reinforced composites, such as stiffness, compression strength, and fatigue resistance, are sensitive to fiber alignment. In this paper, we use structure tensor analysis on CT images characterize the orientations in three samples unidirectional composites: pultruded carbon, pre-preg non-crimp glass fabric. Our results show that fibers sample more aligned than two o...

The performance of pretensioned, laminated, unidirectional (UD), carbon fiber reinforced polymer (CFRP) straps, that can potentially be used for example as bridge deck suspender cables or prestressed shear reinforcements concrete slabs and beams, was investigated at elevated temperatures. This paper aims to elucidate the effects temperature specifically on tensile pin-loaded straps. Two types t...

PURPOSE The aim of this study was to compare the flexural strength of polymethyl methacrylate (PMMA) and bis-acryl composite resin reinforced with polyethylene and glass fibers. MATERIALS AND METHODS Three groups of rectangular test specimens (n = 15) of each of the two resin/fiber reinforcement were prepared for flexural strength test and unreinforced group served as the control. Specimens w...

Binder stabilized preforms are getting increased attention in the wind turbine industry with aim to increase automation production of large blades. In this context a preform is stack dry unidirectional glass fiber non-crimp fabrics (UD-NCF), which consolidated using polymeric binder. The manufactured separate mold, and subsequently placed main blade mold. During placement preforms, wrinkling ma...