STUDY ON MECHANICAL BEHAVIOR OF COMPOSITE LAMINATE WITH CONTINUOUS LARGE CUTOUTS UNDER TENSION

Abstract

Abstract: Large cutout was usually needed to meet the equipment installation, inspection and maintenance requirements when composite laminates were used as the main bearing components in aircraft structure. However, when the fibers were cut off, the local stress and deformation of the structure were discontinuous, which lead to stress concentration and cause complex mechanical behavior. Experiments and finite-element-method (FEA) had been conducted to investigate the deformation, load transmission and stress concentration behavior of a stiffened composite laminate with two large elliptical cutouts under tension. Damage mode and fracture load of the structure were predicted. The results indicate that strain distribution nearby the large cutouts of composite laminate is complicated. The damage will easily occur around the cutout area due to stress concentration and damage mode are diversified. Although the ultimate strength of the laminate is determined by fiber tensile damage and failure but the premature fiber extrusion damage caused by Poisson effect in cutout area cannot be ignored.

Key words: composite laminate, large cutouts, tensile experiment, failure analysis

CLC Number:

TB332

WANG Li-li, FU Jian-wei, XUE Jun-chuan, LI Xin-xiang. STUDY ON MECHANICAL BEHAVIOR OF COMPOSITE LAMINATE WITH CONTINUOUS LARGE CUTOUTS UNDER TENSION[J]. Fiber Reinforced Plastics/Composites, 2019, 0(3): 26-31.

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