Colloquium: João Francisco Gois de Freitas (ASM)

30 september 2019 13:00 - Locatie: Lecture Room D, Faculty of Aerospace Engineering, Kluyverweg 1, Delft.

Damage progression on FRP adhesively bonded single lap joints under quasi-static tension

Adhesively bonded joints had proven to outperform their mechanically fastened joints counterparts, as they present a more structurally efficient method of load transfer, lower stress concentrations and better fatigue performance at reduced weight. Such joints made of Fiber Reinforced Polymer (FRP) adherends and bonded with an epoxy adhesive layer sustain a substantial amount of damage, from failure onset to ultimate failure.
A well-established set of Damage Progression Models (DPMs) in the framework on the Continuum Damage Models (CDMs) were developed as a tool to predict the global response, damage initiation load and ultimate load of the specimens. For the validation of the DPMs, the numerical results were compared against the data of an already published experimental study. Four different adherend layup sequences were studied based on data extracted from the mechanical testing, Digital Image Correlation (DIC) and Acoustic emission (AE).
Satisfactory correlations were found in terms of global behavior, damage initiation load and ultimate load. Nonetheless, the numerical results show a smeared representation of damage, mostly due to the homogenization of the anisotropic material in the modeling process.