Identification of the dynamic characteristics of a viscoelastic, nonlinear adhesive joint

Modification and evaluation of a FRF-based model updating method for identification of viscoelastic constitutive models for a nonlinear polyurethane adhesive in a bonded joint

“…After the original work of Fox and Kapoor [11], the formulation of the IEM has been presented by many researchers for instance by Naraghi and Nobari [7] and here is repeated in brief to be compatible with the present paper notation. Using the same notation as in Section 3, the complex eigen-value problem for the FE model can be written as: (12) where and are the r-th eigen-value and eigen-vector of the model and is normalized such that (13) Differentiating Eq.…”

Nonlinear viscoelastic constitutive model identification for a polyurethane adhesive in a bonded joint using structural dynamic model updating

“…The density of the beam was determined by measuring the weight of the beam before bonding as 7800 kg m -3 and the density of the adhesive material was obtained from the manufacturer's data as 1160 kg m -3 . For the beam and adhesive the Poisson's ratios of 0.3 and 0.44 were assumed, respectively (Naraghi and Nobari, 2015). In the FE model of the bonded beam, perfect bonding is assumed between the adhesive layer and the beam and was introduced to the FE model by merging adjacent nodes of the beam and the adhesive layer on the bonding surface.…”

“…Also, the same authors, Nobari and Jahani (2009) introduced a modification to the modal based direct model updating method to indentify damping characteristics of the same adhesive in bending and shear modes of vibration. Recently, Naraghi and Nobari (2015) have identified the mechanical characteristics of an adhesive using eigenvalues of the system and Inverse Eigen-sensitivity Method (IEM) and experimental data. They illustrated the stiffness softening characteristic of the adhesive and tuned the Standard Linear Solid model (SLS) to represent the adhesive viscoelastic behavior.…”

A Critical Review of Nonlinear Damping Identification in Structural Dynamics: Methods, Applications, and Challenges

“…For example, harmonic balance nonlinearity identification (HBNID) was employed in systems such as civil engineering, actuators, bioengineering devices, sensors, and robotics [ 59 ]. Furthermore, the frequency response functions (FRFs) have been widely utilized to study nonlinear damping in adhesive joints [ 60 , 61 ].…”