ETD

Archivio digitale delle tesi discusse presso l'Università di Pisa

Tesi etd-04082016-191049


Tipo di tesi
Tesi di laurea magistrale
Autore
MENCATTELLI, LORENZO
URN
etd-04082016-191049
Titolo
Experimental and Numerical Studies in Delamination of CFRP with embedded FBGs under various I and II fracture modes
Dipartimento
INGEGNERIA CIVILE E INDUSTRIALE
Corso di studi
INGEGNERIA AEROSPAZIALE
Relatori
relatore Ing. Lazzeri, Roberta
relatore Prof. Botsis, John
Parole chiave
  • optical fiber
  • Mode II
  • Mixed Mode I-II
  • friction
  • Fracture toughness
  • ERR
  • crack monitoring
  • carbon composite
  • bridging
  • 4ENF test
  • R-curve
Data inizio appello
26/04/2016
Consultabilità
Non consultabile
Data di rilascio
26/04/2086
Riassunto
An experimental evaluation of the parameters characterizing the delamination process for an unidirectional carbon fiber reinforced epoxy composite laminate, under different I and II opening modes is presented, followed by a statistical analysis of the experimental data for each loading condition with the final aim of evaluating the critical fracture toughness and the propagation values for each mode mixity. Special attention is given to the influence of bridging fibers on Mixed Mode I-II tests.
Optical fiber sensors are embedded in a carbon fiber reinforced epoxy composite to obtain strain measurements along the crack path at different crack lengths. A comparison of the experimental strains with numerical models to quantify the influence of fiber bridging upon the sample stiffness is done.
Subsequently it is studied the influence of friction coefficients on Mode II (4ENF) pure tests and finally an empirical method is developed for crack front identification in 4ENF tests by means of an embedded optical fiber sensor placed far away from the fracture surfaces.
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