3.1.10.64. ElastomericX Element

This command constructs a three-dimensional elastomeric bearing element that formulates all six directional material models internally from geometric and rubber properties. It extends the ElastomericBearingBouc-Wen Element formulation without requiring user-supplied uniaxial materials. Use with -ndm 3 -ndf 6.

element ElastomericX $eleTag $Nd1 $Nd2 $Fy $alpha $Gr $Kbulk $D1 $D2 $ts $tr $n <$x1 $x2 $x3 $y1 $y2 $y3> <$kc> <$PhiM> <$ac> <$sDratio> <$m> <$cd> <$tc> <$tag1> <$tag2> <$tag3> <$tag4>

Argument	Type	Description
$eleTag	integer	unique element tag
$Nd1 $Nd2	integer	end nodes
$Fy	float	yield strength
$alpha	float	post-yield stiffness ratio
$Gr	float	shear modulus of elastomer
$Kbulk	float	bulk modulus of rubber
$D1	float	internal diameter
$D2	float	outer diameter excluding cover thickness
$ts	float	single steel shim layer thickness
$tr	float	single rubber layer thickness
$n	integer	number of rubber layers
$kc	float	cavitation parameter (optional; default 10.0)
$PhiM	float	damage parameter (optional; default 0.5)
$ac	float	strength reduction parameter (optional; default 1.0)
$sDratio	float	shear distance from iNode as fraction of length (optional; default 0.5)
$m	float	element mass (optional; default 0.0)
$cd	float	viscous damping parameter (optional; default 0.0)
$tc	float	cover thickness (optional; default 0.0)
$tag1	integer	include cavitation and post-cavitation (optional; default 0)
$tag2	integer	include buckling load variation (optional; default 0)
$tag3	integer	include horizontal stiffness variation (optional; default 0)
$tag4	integer	include vertical stiffness variation (optional; default 0)

Note

1. Characteristic strength is \(Q_d = F_y(1-\alpha)\); do not confuse with \(F_y\).

2. Use Parameters Element Recorder to obtain cavitation force; buckling capacity; vertical stiffness; and horizontal stiffness.

Example

1. Tcl Code

element ElastomericX 1 1 2 100.0 0.1 0.8 2.0e9 0.0 0.6 0.003 0.01 20 0 1 0 1 0 0 10.0 0.5 1.0 0.5 0.0 0.0 0.0 1 0 0 0

2. Python Code

element('ElastomericX', 1, 1, 2, 100.0, 0.1, 0.8, 2.0e9, 0.0, 0.6, 0.003, 0.01, 20,
        0, 1, 0, 1, 0, 0, 10.0, 0.5, 1.0, 0.5, 0.0, 0.0, 0.0, 1, 0, 0, 0)

Code developed by: Manish Kumar, University at Buffalo, SUNY