Methodology to analyse aerospace structures repaired with a bonded composite patch

Abstract

Adhesively bonded composite repair of metallic structures is one of the candidate technologies that has enormous potential in the ageing aircraft. A computational tool to analyse the repaired aerospace structure using an adhesively bonded composite patch is presented. This involves the three-layer technique based on the two-dimensional finite element method for adhesively bonded composite patch repair of cracked structures. This technique is capable of characterizing the crack growth and debond growth behaviour, as well as predicting the fatigue life extension of the repaired structure with a perfectly or imperfectly bonded patch. Also, the thermal effects which may develop during bonding or during service and the non-linear material behaviour of the adhesive are incorporated in this technique. The results from the three-layer technique show good agreement with experimental results as well as a previous investigator's published numerical results. Besides the accuracy of the technique, the advantage of the twodimensional three-layer technique is cost-effectiveness when compared with the three-dimensional finite element or performing expensive experiments on various patch configurations for design purposes. An overview of the three-layer technique to investigate a cracked metallic plate repaired with bonded composite patch is presented in this paper.

Numerical Analysis of the Bonded Composite Shape Effects under Thermal Loading in Aircraft Structures

“…This technology involves, the use of advanced fiber composite patches (such as boron/epoxy or graphite/epoxy) bonded with structural film adhesives, they have been successfully used in the aircraft industry [1][2][3][4][5] offering significant advantages over traditional repair methods (riveting, fastening, welding) [6,7] .Afterward, this technology was used for repairing structures in the industries [8] . Using the FEM technique is the best choice to analyze the effect of different repair process parameters on the overall performance of structures repaired by polymer composite patches [9][10][11][12].…”

The optimization thickness of single/double composite patch on the stress intensity factor reduction

“…The success of this repair is based on the many studies carried out by several researchers over the past two decades. [8][9][10][11] The structures of the aerospace industry are quite often subject to conditions of fatigue loading. Therefore, the investigation on the behavior of crack growth in the reinforced structures by patch has been the main priority in the majority of previous studies.…”