English Abstract
Abstract:
Bonded joints used in wing sections and frames of aircraft structures are mostly exposed to
cyclic loadings instead of static ones during their services. Bending types of dynamic loadings are
mostly encountered. In this study, the fatigue response of a single lap joint (SLJ) exposed to bending
loading was studied with the developed advanced finite-element (FE) model. The cohesive zone
model describing the behaviour of the adhesive layer used the damage mechanism, where static and
fatigue damages were linked to each other; i.e., the total damage was accumulated because of material
deterioration and cyclic plastic separation. This enabled us to predict the fatigue characteristics
including the finite fatigue life, crack propagation rate using Paris law. The model was implemented
via a user-defined UMAT subroutine offered in ABAQUS-Standard. The numerical model was
validated by experiments available in the literature. The fatigue performance of an SLJ subjected
to bending loading was investigated for different lap joint configurations. A smaller bending load,
a thicker adherend or a longer overlap length (OL) led to enhanced fatigue life. For instance, the
fatigue life was observed to increase up to 50 times for a 66% increase in OL.
