Fracture analysis of Kevlar-49/epoxy and e-glass/epoxy doublers for reinforcement of cracked aluminum plates

Ananth Ram Mahanth Kasavajhala, Linxia Gu

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Adhesively bonded composite patch repair is efficient means to regain load carrying capacity, alleviate the crack growth, and improve the service life of the damaged structure. In this paper, three dimensional finite element models are developed to examine the fracture behavior of a single edge V-notched Aluminum plate repaired with Kevlar-49/epoxy or e-glass/epoxy pre-preg patches on both sides. Contour integral method was used for evaluating the stress intensity factor (SIF), an indicator of the crack stability. The load transfer mechanisms, stress distribution, damage variable (D), and crack mouth opening displacement (CMOD), were also presented to estimate the effectiveness of composite patch repair. The influence of the patch material, crack length and the adhesive thickness has been investigated. Results have shown that the crack induced damage increased nonlinearly with a larger crack size. With the composite patch repairs, SIF is reduced to 1/7-1/10 of that of the bare plate and CMOD decreased by 79%. The damage variable is reduced significantly and the load capacity is increased. A thinner adhesive layer results in a higher percentage of load shared by the composite patch.

Original languageEnglish (US)
Pages (from-to)2090-2095
Number of pages6
JournalComposite Structures
Volume93
Issue number8
DOIs
StatePublished - Jan 1 2011

Fingerprint

Aluminum
Reinforcement
Cracks
Glass
Repair
Composite materials
Stress intensity factors
Adhesives
Regain
Load limits
Service life
Kevlar 49
Stress concentration
Crack propagation
Loads (forces)

Keywords

  • A. Structural composites
  • C. Finite element analysis (FEA)
  • C. Stress concentrations
  • C. Stress transfer
  • Damage variable

ASJC Scopus subject areas

  • Ceramics and Composites
  • Civil and Structural Engineering

Cite this

Fracture analysis of Kevlar-49/epoxy and e-glass/epoxy doublers for reinforcement of cracked aluminum plates. / Kasavajhala, Ananth Ram Mahanth; Gu, Linxia.

In: Composite Structures, Vol. 93, No. 8, 01.01.2011, p. 2090-2095.

Research output: Contribution to journalArticle

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