Cohesive/adhesive failure interaction in ductile adhesive joints Part II: Quasi-static and fatigue analysis of double lap-joint specimens subjected to through-thickness compressive loading

Abstract

a b s t r a c tThis paper proposes a new methodology for the finite element (FE) modelling of failure in adhesively bonded joints. Cohesive and adhesive failure are treated separately which allows accurate failure predictions for adhesive joints of different thicknesses using a single set of material parameters. In a companion paper (part I), a new smeared-crack model for adhesive joint cohesive failure was proposed and validated. The present contribution gives an in depth investigation into the interaction among plasticity, cohesive failure and adhesive failure, with application to structural joints. Quasi-static FE analyses of double lap-joint specimens with different thicknesses and under different levels of hydrostatic pressure were performed and compared to experimental results. In all the cases studied, the numerical analysis correctly predicts the driving mechanisms and the specimens' final failure. Accurate fatigue life predictions are made with the addition of a Paris based damage law to the interface elements used to model the adhesive failure.

Mechanical behaviour of thermoplastic composites spot-welded and mechanically fastened joints: A preliminary comparison

“…In this study, both of the load values on these two points were noted, hereafter mentioned as onset failure load (OFL) and ultimate failure load (UFL), to evaluate the load-carrying capability of the joints. The OFL was calculated by the bilinear approximation method, which is commonly used in numerical modelling to characterize the structural failure and proved to provide good fits to the experimental L-D curves [28,29]. An example is shown on representative DLS (a) and PT (b) L-D curves for mechanically fastened joints in Fig.…”

Progressive failure mechanism of laminated composites under fatigue loading

“…Belnoue et al. 17 employed the Paris law to represent fatigue in an interface element based on change in strain energy release rate, ΔG. The crack growth rate, ∂normala/∂normalN, was assumed to be a function of change in strain energy release rate, ΔG, in the crack tip within each cyclic loading and can be written as: where G C is the critical fracture energy, C and m are fitting parameters determined experimentally.…”

“…The change in strain energy rate during fatigue loading can be calculated from the instantaneous maximum strain energy and the load ratio R as 17 where R is the load ratio and is defined by the user input in the numerical model. G max is calculated from the traction–separation curve of the cohesive zone model (CZM) for each fatigue cycle.…”

Parametric Study of Flexural Strengthening of Concrete Beams with Prestressed Hybrid Reinforced Polymer

“…Δmf is the failure displacement jump corresponding to complete debonding. Δm0 is determined by damage criteria as follows [19]. (〈Δn〉Δn0)2+(ΔsΔs0)2=1…”