The

damping constant for normal contact of the sand was set as 0.1, and the

damping constant for tangential contact was half of the former.

The

damping constant [h.sub.s] of the s order vibration mode is expressed by the following formulas (12) and (13):

The modal elastic constant and the

damping constant are therefore given as follows:

Where c is the propagating velocity of the wave, [eta] is the viscous

damping constant for the current media the wave is traveling in, and |r - [r.sub.k]| is the distance from source to receiver point, f--frequency of calculation.

where c is a viscous

damping constant, [rho] is the soil density, and V is the shear wave velocity.

Therefore, from the perspective of reducing the internal force in tower bottom foundation, the optimal effect can be achieved when damping coefficient C is in the range of 7,500~15,000 kNx[(s/m).sup.[xi]] and

damping constant [xi] is in the range of 0.3~0.5.

[9] suggested that the radiation

damping constant in the zeropoint field as [[GAMMA].sub.z] which is not necessarily equal to the

damping constant [[GAMMA].sub.a] of Larmor formula for power radiated by an accelerated charged particle.

Jankowski [2] puts forward a nonlinear viscoelastic model based on the Hertz impact model and then derived the expression of the

damping constant of the nonlinear viscoelastic impact model.

(1) which introduces the relationship between the bending moment (M (x,t)) and deflected shape (w(x,t)) of the beam, equivalent flexural stiffness and

damping constant of the beam is extracted:

where [k.sub.s] is the linear spring stiffness constant, [b.sub.s] is the linear damper constant, [k.sub.snl] is the nonlinear spring stiffness, and [b.sub.snl] is the nonlinear

damping constant. The motion of the vehicle over a bump that restricts the wheel travel within a given range and prevents contact between the tyre and the vehicle body is effectively modeled by the nonlinear spring force, [f.sub.k].

where n is the

damping constant, which indicates the growth rate of losses with the increasing distance d.

The displacement of the pendulum head ([theta](t)) is evaluated as a function of time with a

damping constant [lamda] using equation 3.