On the torsional wave dispersion in a hollow sandwich circular cylinder made from viscoelastic materials

Genelleştirilmiş Rayleigh Dalgaların Viskoelastik Tabakalı Yarı-uzay Ortamlarda Sönümlenmesi

“…If the selected two unknowns are 1 kh and  , then we can determine the wave propagation velocity c as a result of the solution to the dispersion equation. Note that this approach was already made in the papers by Akbarov and Negin [28], Akbarov and Kepceler [22], Akbarov et al [23,24] under which the wave attenuation coefficient  was determined according to the expressions given in the references Ewing et al [29] and Kolsky [30]. However, if the selected two unknowns are c and Thus, in the present paper we investigate the attenuation of the generalized Rayleigh waves within the scope of the foregoing algorithm.…”

“…At the same time, as in the papers [20,22] introducing the following dimensionless rheological parameters: (24) the following expressions can be obtained for the long-term values of the mechanical  which enter into the equation (15): corresponds to the 'standard viscoelastic body' model (or the model by Kelvin). Consequently, according to the above expressions, the effect of the viscoelasticity of the m-th material on the attenuation curves will be estimated through these three dimensionless rheological parameters.…”

On attenuation of the seismic Rayleigh waves propagating in an elastic crustal layer over viscoelastic mantle

“…Here, Γ(x) is the Gamma function and the constants α (m) , β The mechanical meanings of these rheological parameters are explained in the papers by Akbarov (2014) and Akbarov and Kepceler (2015). Finally, using relations (9 and 18), we obtain:…”

“…Therefore, they cannot actually describe the real and complicated behaviour of viscoelastic materials. These considerations directed the authors to study the near-surface wave dispersion and attenuation of a viscoelastic covered half-space utilising a more realistic mathematical model (Akbarov and Negin 2017b) by using Rabotnov (1980) fractionalexponential operators which are used in the papers by Akbarov (2014Akbarov ( , 2015, Akbarov and Kepceler (2015), Akbarov et al (2016a, b) and Kocal and Akbarov (2017) in the first place. This study, in that sense, is actually an extension of the authors' previous studies (Negin et al 2014;Negin 2015; Akbarov and Negin 2017a) on dispersion of the generalised Rayleigh waves in an initially stressed elastic covered half-space to the viscoelastic case, where the constitutive relations of the materials of the covering layer and the half-space are described through the fractional-exponential operator by Rabotnov (1980).…”

Polimer-Viskoelastik Malzemeli Boru Hatlarındaki Eğilme Dalgalarının Dispersiyonu

“…Akbarov ve Kepceler [8], üç katlı içi boş silindir için burulma dalgalarının yayılımını incelemişlerdir. Bu çalışmada viskoelastik malzemeden yapılmış borudaki eksenel simetrik burulma dalga yayılımı, Rabotnov [9] tarafından fraksiyonel eksponansiyel operatörler ile verilen reolojik bağıntılar kullanılarak araştırılmıştır.…”