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A conventional plate-type viscoelastic damper (VED) can easily crack at the interfaces of steel plates and viscoelastic components. In the present work, grooved VEDs, which are a new type of interfacial enhanced VEDs with interfacial grooves, are designed to improve the damping capacity and anti-cracking ability of conventional dampers. The dynamic property experiments of the normal and grooved VEDs are carried out and the interfacial cracking failure of the VEDs are simulated and analyzed by using bilayer cohesive constitutive model with ABAQUS. The grooved VED exhibits excellent dynamic performance and energy dissipation capacity at different temperatures, frequencies, and displacement amplitudes. Experiments and finite element analysis prove that the energy dissipation performance and interfacial bonding strength of the grooved VED are effectively improved. A modified fractional standard linear solid model, in which the Payne effect and temperature–frequency equivalent principle are combined and implemented, is proposed. This model can portray the influence of the excitation displacement, surrounding temperature and external excitation frequency on damper properties at the same time. The fillers and molecular chains affections at micro- and meso-scale are also taken into account. The model’s numerical calculations and experimental results comparisons present that the modified fractional standard linear solid model has sufficient accuracy and performs well in depicting the dynamic properties of the interfacial grooved VED. The errors between the theoretical and experimental values of G1 and G2 for the grooved VED are mostly within 20% at representative conditions. The interfacial groove structures can well enhance the interfacial bonding and improve the service life of conventional dampers. The modified fractional standard linear solid model is simple and has clear physical meanings for each macro/micro parameters, making it convenient for application in engineering practice. The present research is of great significance in improving the work stability of VEDs and promoting the application of viscoelastic damping technology.
A growing body of evidence suggests that limited accuracy can be expected from analytical and computational tools relying on linear viscoelasticity for the prediction of rolling resistance in real systems presenting material and geometric nonlinearities. A set of experimental data for the viscoelastic resistance to motion incurred by a rigid sphere rolling between two parallel sheets of rubber, in realistic in-service conditions, was determined, in a previous work [Zéhil and Gavin, 2019]. The tests involved different elastomers (a Urethane rubber and a Neoprene rubber) and different sheet thicknesses, ball diameters, loading levels and rolling speeds. The accuracy of linear models in predicting such practical data is assessed in this work. To this aim, the elastomers are described by general linear viscoelastic models whose master-curves are characterized by: (i) High Frequency Thermo-Viscoelastic Spectroscopy, under very small strain amplitudes and (ii) Dynamic Mechanical Analysis under relatively larger deformations. In both cases, rolling resistance predictions are obtained using computational tools based on linear viscoelasticity [Zéhil and Gavin, 2013a, 2013b] and compared to the measurements. Conclusions are drawn regarding: (i) the practical limitations of linear rolling resistance models and (ii) influences of nonlinearities such as those due to large deformations, to the Mullins effect [Mullins, 1969] and to the Payne effect [Payne, 1962], on predictions.