# Velocity and Pressure Dependent Friction

This command is used to construct a VelPressureDep friction model object.

```tcl frictionModel VelPressureDep $frnTag $muSlow $muFast0 $A $deltaMu $alpha $transRate ```
frnTag

unique friction model object tag

muSlow

coefficient of friction at low velocity

muFast0

initial coefficient of friction at high velocity

A

nominal contact area

deltaMu

pressure parameter calibrated from experimental data

alpha

pressure parameter calibrated from experimental data

transRate

transition rate from low to high velocity


## Examples

frictionModel VelPressureDep 1 0.085 0.163 7.0686 0.05 0.08 0.77


REFERENCES:

[1] Tsopelas P., and Constantinou M. C. (1996). "Experimental Study of FPS System in Bridge Seismic Isolation." Earthquake Eng. and Structural Dynamics, VOL. 25, 65-78.

[2] Constantinou M. C., Tsopelas P., Kasalanati A., and Wolff E. D. (1999). Property Modification Factors for Seismic Isolation Bearings. Technical Report MCEER-99-0012, University of Buffalo, Buffalo, New York.


RELATED TO:


Code Developed by: Andreas Schellenberg, University of California, Berkeley.