In this study, we mainly employ a proper orthogonal decomposition (POD) to lower the dimension for unknown Crank–Nicolson finite element (FE) (CNFE) solution coefficient vectors of viscoelastic wave (VW) equation so as build reduced-dimension recursive CNFE (RDRCNFE) algorithm, adopt matrix analysis analyze stability together with errors RDRCNFE solutions, and utilize some numerical experimenta...

Conventional seismic rehabilitation methods may not be suitable for some buildings owing to their high cost and time-consuming foundation work. In recent years, viscoelastic dampers (VEDs) have been widely used in many mid- and high-rise buildings. This study introduces a viscoelastic passive control system called rotary rubber braced damper (RRBD). The RRBD is an economical, lightweight, and e...

The propagation of ultrasonic guided waves in viscoelastic isotropic material has been investigated. Based on the plane theory, a numerical model of the guided waves propagating is developed in the frequency domain by employing the SFEM (spectral finite element method). To verify the proposed method, thin bitumen on the steel substrate is examined and compared with the single plate in terms of ...

the rheological properties of four different kuwaiti crude oils in the presence of polyacrylamide (paa) were investigated. paa was varied at three different concentrations of 25, 50, and 75 ppm to study the viscoelastic properties in the untreated samples. four different temperatures (25, 30, 35, and 40 °c) were used to evaluate different viscoelastic parameters of the treated and untreated kuw...

little is known about the interaction of tissue conditioners and modeling plastics. this study evaluates the influence of a variety of commercial tissue conditioners on alteration of viscoelastic properties of modeling plastics.in this in vitro study, the dynamic viscoelastic properties of four commercially available tissue conditioners (tc), visco-gel (vg), gc soft-liner (sl), fitt (ft), and c...

The paper presents a Semi-Analytical Finite Element (SAFE) formulation coupled with a 2.5D Boundary Element Method (BEM) for the computation of the dispersion properties of viscoelastic waveguides with arbitrary cross-section and embedded in unbounded isotropic viscoelastic media. Attenuation of guided modes is described through the imaginary component of the axial wavenumber, which accounts fo...

Deformation brings out important features of viscoelastic behaviour in polymers. To achieve a better understanding of the underlying phenomena, molecular dynamics simulations have been performed for oneand two-phase polymeric materials created on the computer. An external force was applied to the materials and their response followed as a function of time. The mechanical properties were found t...

Composite materials, especially polymer matrix composites, have been intensively studied for energy absorption applications. When the temperature is close to or higher than the glass transition temperature (Tg), the polymer matrix is usually viscoelastic. With an external loading, either dynamic or quasi-static, the relaxation of the network polymer chains would cause a considerable energy diss...

Abstract In this work a procedure to compute the dispersion curves for one dimensional viscoelastic waveguides exploiting the finite element based global mass matrix and complex stiffness matrix is proposed. The global matrices of a finite length portion of the waveguide, the unit cell, are post-processed by enforcing Bloch-type boundary conditions along the wave propagation direction and next ...

The influence of Multi-walled carbon nanotubes (MWCNTs) on mechanical and viscoelastic properties epoxy-based Glass/Carbon fiber hybrid composite were investigated. In the present work, a small amount MWCNTs in range 0.25 - 1 wt. % is directly mixed epoxy/matrix material. Different composites prepared by hand lamination method placing Glass Carbon reinforcements alternatively matrix. Tensile, B...