My suggestion would be , to look soil dynamics books to get the concept.
The following excerpt is copy and paste from Practical Soil Dynamics (by MILUTIN SRBULOV )
... the following static stiffness and viscous damping coefficients shown in Table 1.2. Static stiffness coefficient is the ratio between applied force and caused displacement and viscous damping coefficient is the ratio between applied force and caused velocity of movement.
Use it up, wear it out;
Make it do, or do without.