Thesis-2004-Maranon.pdf (16.72 MB)
Characterising delamination in composite materials: a combined genetic algorithm - finite element approach
thesis
posted on 2011-01-10, 12:23 authored by Alejandro MaranonA novel delamination identification technique based on a low-population genetic
algorithm for the quantitative characterisation of a single delamination in
composite laminated panels is developed, and validated experimentally The
damage identification method is formulated as an inverse problem through
which system parameters are identified. The input of the inverse problem, the
central geometric moments (CGM), is calculated from the surface out-of-plane
displacements measurements of a delaminated panel obtained from Digital
Speckle Pattern Interferometry (DSPI). The output parameters, the planar location,
size and depth of the flaw, are the solution to the inverse problem to
characterise an idealised elliptical flaw. The inverse problem is then reduced
to an optimisation problem where the objective function is defined as the L2
norm of the difference between the CGM obtained from a finite element (FE)
model with a trial delamination and the moments computed from the DSPI
measurements. The optimum crack parameters are found by minimising the
objective function through the use of a low-population real-coded genetic algorithm
(LARGA). DSPI measurements of ten delaminated T700/LTM-45EL
carbon/epoxy laminate panels with embedded delaminations are used to validate
the methodology presented in this thesis.
History
School
- Mechanical, Electrical and Manufacturing Engineering
Publisher
© Alejandro MaranonPublication date
2004Notes
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.EThOS Persistent ID
uk.bl.ethos.416603Language
- en