3.1.10.60. TripleFrictionPendulum Element

This command constructs a triple friction pendulum bearing element using the series model of Dao et al. (2013). Three friction model objects define sliding behavior at the three active interfaces; four uniaxialMaterial Command objects define axial and rotational behavior. For the original geometry-based TFP element see TripleFrictionPendulumBearing Element. For heating effects see TripleFrictionPendulumX Element.

element TripleFrictionPendulum $eleTag $iNode $jNode $frnMdl1 $frnMdl2 $frnMdl3 $matP $matT $matMy $matMz $L1 $L2 $L3 $Ubar1 $Ubar2 $Ubar3 $W $Uy $Kvt $minFv $tol

Argument	Type	Description
$eleTag	integer	unique element tag
$iNode $jNode	integer	end nodes
$frnMdl1 $frnMdl2 $frnMdl3	integer	tags of three friction models
$matP	integer	uniaxial material tag for axial behavior
$matT	integer	uniaxial material tag for torsion
$matMy $matMz	integer	uniaxial material tags for moments about local y and z
$L1 $L2 $L3	float	effective pendulum lengths for the three sliding interfaces
$Ubar1 $Ubar2 $Ubar3	float	displacement capacities at the three interfaces
$W	float	axial load on bearing
$Uy	float	yield displacement for shear behavior
$Kvt	float	vertical stiffness
$minFv	float	minimum vertical force for friction activation
$tol	float	convergence tolerance for internal equilibrium

Note

1. Use with -ndm 3 -ndf 6.

2. P-Delta moments are transferred entirely to the concave sliding surface (iNode).

Example

1. Tcl Code

element TripleFrictionPendulum 1 1 2 1 2 3 10 11 12 13 2.0 2.0 4.0 0.5 0.5 1.0 500.0 0.01 1.0e6 10.0 1.0e-8

2. Python Code

element('TripleFrictionPendulum', 1, 1, 2, 1, 2, 3, 10, 11, 12, 13,
        2.0, 2.0, 4.0, 0.5, 0.5, 1.0, 500.0, 0.01, 1.0e6, 10.0, 1.0e-8)

Code developed by: Nhan Dao, University of Nevada, Reno