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LUCAS VIGNOLI
MARCELO SAVI

Abstract

STRUCTURES MADE OF COMPOSITE MATERIALS HAVE BEEN WIDELY USED DUE TO ADVANTAGES OF EQUIVALENT PROPERTIES FROM THE JOINING OF DIFFERENT MATERIALS. ANISOTROPY AND HETEROGENEITY ARE ESSENTIAL CHARACTERISTICS OF COMPOSITE MATERIALS THAT MAKE THEIR MECHANICAL MODELLING HARD AND COMPLEX. THIS PAPER DEALS WITH A MULTISCALE APPROACH TO MODEL THICK-WALLED LAMINATE CYLINDER WITH INTERNAL PRESSURE. BASED ON THAT, MICROMECHANICS DEFINE MATERIAL HOMOGENIZATION CONSIDERING TWO STEPS: DETERMINATION OF EQUIVALENT PROPERTIES OF ONE LAMINA FROM MATRIX AND FIBER PROPERTIES; AND DETERMINATION OF ANISOTROPIC HOMOGENEOUS PROPERTIES OF THE LAMINATE BUILT WITH A SET OF LAMINAE. ON THE OTHER HAND, MACROMECHANICS DETERMINES STRESS AND FAILURE ANALYSIS. MICROMECHANICS APPROACH IS EMPLOYED USING THE MORI-TANAKA MODEL TO OBTAIN THE EQUIVALENT ELASTIC PROPERTIES WHILE THE BRIDGING MODEL IS EMPLOYED TO OBTAIN STRENGTH PROPERTIES OF EACH LAMINA FROM THE CONSTITUENT PROPERTIES. MOREOVER, THE ASYMPTOTIC HOMOGENIZATION IS EMPLOYED THROUGH THE WALL’S THICKNESS TO COMPUTE THE EFFECTIVE PROPERTIES OF THE HOMOGENIZED ANISOTROPIC TUBE. CONCERNING MACROMECHANICS, THE LEKHNITSKII FORMALISM IS USED TO OBTAIN THE ELASTIC SOLUTION OF THE STRESS AND STRAIN DISTRIBUTIONS. THE STRAIN BASED TSAI-WU FAILURE CRITERION IS APPLIED. THREE DIFFERENT PRESSURE VESSEL CONFIGURATIONS ARE ANALYZED ACCORDING TO THE END CONDITIONS: RESTRAINED-ENDS, OPEN-ENDS AND CLOSED-ENDS. ANGLE-PLY LAMINATES MADE OF CARBON FIBERS AND EPOXY MATRIX ARE CONSIDERED TO EVALUATE THE INFLUENCE OF LAY-UP ANGLE, FIBER VOLUME FRACTION, WALL THICKNESS AND END-CONDITIONS. THE OPTIMUM ANGLES AS WELL AS THE MAXIMUM INTERNAL PRESSURE ARE OBTAINED AND A PARAMETRIC ANALYSIS IS PRESENTED.

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Section
MecSol 2017 Joinville