Numerical analysis on load-bearing capacity and damage of double scarf adhesive joints subjected to combined loadings of tension and bending

Abstract

a b s t r a c tThe load-bearing capacity and the damage level of the double scarf joint (DSJ) under combined loadings of tension and bending were investigated numerically, which takes into account the effects of scarf angle and adhesive type. A finite element method (FEM), which includes a mixed-mode cohesive zone model (CZM) with a bilinear shape, was employed to govern the interface separation behaviors. At the point corresponding to the ultimate loading, it was observed that the interface damage level of DSJ with the ductile adhesive is higher and more uniform than that of the joint with the brittle one. More than that, the numerical results illustrated that the failure of DSJ is controlled not only by the ultimate loading, but also by the applied displacement until complete failure. Therefore, the failure energy, which is defined as the integral of the loading with respect to the displacement, was adopted to estimate the joint performance. Subsequently, the numerical results showed that the failure energy of the joint with the ductile adhesive is higher than that of the joint with the brittle one. Furthermore, all the discussed characteristic parameters of a DSJ with a given adhesive, including ultimate loading, the von-Mises equivalent stress and interface damage level corresponding to the ultimate loading, and the failure energy, were inversely proportional to the scarf angle. Finally, through comparing with the existing experimental measurements, the adoptive method was validated.

RETRACTED ARTICLE: Analytical and FE modelling of bidirectional stress distributions in adhesively bonded step-lap joints under thermo-mechanical loads

“…Modifying the joint configuration drives to a change in the joint interface stress distribution and then the joint strength. In order to enhance bond properties joint geometry is tailored and various kinds of joint configuration are proposed for adhesive joints namely stepped [7], scarf [8,9], double scarf [10] and reverse bent [11]. For thick laminate, all of these bonded joint methodologies (except reverse bent) are suitable.…”

Interfacial Stress Analysis of Adhesively Bonded Lap Joint

“…The reduction of peel stress is due to the elimination of the eccentricities of applied loads, while shear stress is reduced by removing the differential straining effect [6]. The scarf joint is considered as the best in terms of strength for the same bonding region, by further reducing the stress concentration because of the elimination of the geometry discontinuity, which appears in the lap joints [7]. Although, adhesively bonded joints have been used more often than that of mechanical joints in connecting the structural components owing to their advantages such as more uniform interfacial stress distributions, capability of joining different materials and high resistance to fatigue failure [8,9].…”

Experimental and Numerical Investigation of Adhesively Bonded Curved Lap Joints under Three-Point Bending

“…Furthermore, studies on the strength of the adhesive were also carried out under different types of external loads for various types of adhesive joints. For this purpose, various adhesive joint models were subjected to loads such as three-point and four-point bending, and anti-symmetric, and investigations were conducted on what kind of tensile behavior the joint would exhibit in the interface [26][27][28][29].…”