LOCATION-BASED EFFECT OF DECOMPOSITION ON LAMINATED CURVED PLATE STRUCTURES

Abstract

THIS STUDY PRESENTS A FREE VIBRATION ANALYSIS OF THREE DIFFERENT CURVED LAMINATED COMPOSITE PLATES HAVING ENDTO-END DECOMPOSITION UNDER FIXED OPPOSING STRAIGHT EDGES. THE CURVED STRUCTURES HAVE BEEN MATHEMATICALLY MODELED BY EMPLOYING THE CLASSICAL LAMINATED PLATE THEORY AND THE FINITE ELEMENT METHOD TO PERFORM THE LOCATION-BASED EFFECT OF DECOMPOSITION. BESIDES, THE RELATION AMONG THE DECOMPOSITION, CURVATURE CHARACTERISTICS, AND STACKING SEQUENCES IS EXAMINED IN TERMS OF NATURAL FREQUENCIES. FOR THIS PURPOSE, THE ENDTO-END DECOMPOSITIONS ARE DEFINED IN TWO DIFFERENT LEVELS AND RE-POSITIONED ALONG THE CURVED EDGE FOR EACH VIBRATION ANALYSIS. THE FREQUENCY RATIO IS OBTAINED BY PROPORTIONING THE NATURAL FREQUENCY OF THE DAMAGED STRUCTURE TO THAT OF THE HEALTHY STRUCTURE AND CONSIDERED TO INTERPRET THE EFFECTS OF THE DECOMPOSITION LOCATION. CROSS-PLY AND ANGLE-PLY STRUCTURES HAVING ELLIPTIC, CIRCULAR, AND PARABOLIC CURVATURES ARE CONSIDERED. IT IS CONCLUDED THAT THE EFFECT OF THE END-TO-END DECOMPOSITION ON THE NATURAL FREQUENCIES VARIES TO ITS LEVEL, THE STACKING ORDER, AND THE BENDING REGIONS OF THE RELEVANT MODE SHAPE.