Elastomeric Bearing (Plasticity) Element: Difference between revisions

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| '''$y1 $y2 $y3''' || vector components in global coordinates defining local y-axis (optional)
| '''$y1 $y2 $y3''' || vector components in global coordinates defining local y-axis (optional)
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|-
| '''$m''' || element mass (optional), default = 0.0
| '''$m''' || element mass (optional, default = 0.0)
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Revision as of 01:13, 10 March 2010




This command is used to construct an elastomericBearing element object, which is defined by two nodes. The element can have zero length or the appropriate bearing height. The bearing has unidirectional (2D) or coupled (3D) plasticity properties for the shear deformations, and force-deformation behaviors defined by UniaxialMaterials in the remaining two (2D) or four (3D) directions. P-Delta moments are equally distributed to the two end-nodes. If the element has non-zero length, the local x-axis is determined from the nodal geometry unless the optional x-axis vector is specified in which case the nodal geometry is ignored and the user-defined orientation is utilized.

For a two-dimensional problem:

element elastomericBearing $eleTag $iNode $jNode $ke $fy $alpha -P $matTag -Mz $matTag <-orient $x1 $x2 $x3 $y1 $y2 $y3> <-mass $m>

For a three-dimensional problem:

element elastomericBearing $eleTag $iNode $jNode $ke $fy $alpha -P $matTag -T $matTag -My $matTag -Mz $matTag <-orient <$x1 $x2 $x3> $y1 $y2 $y3> <-mass $m>



$eleTag unique element object tag
$iNode $jNode end nodes
$ke initial elastic stiffness
$fy yield strength
$alpha post yield stiffness ratio
-P $matTag tag associated with previously-defined UniaxialMaterial in axial direction
-T $matTag tag associated with previously-defined UniaxialMaterial in torsional direction
-My $matTag tag associated with previously-defined UniaxialMaterial in moment direction around local y-axis
-Mz $matTag tag associated with previously-defined UniaxialMaterial in moment direction around local z-axis
$x1 $x2 $x3 vector components in global coordinates defining local x-axis (optional)
$y1 $y2 $y3 vector components in global coordinates defining local y-axis (optional)
$m element mass (optional, default = 0.0)


NOTE:

If the element has zero length and optional orientation vectors are not specified, the local element axes coincide with the global axes. Otherwise the local z-axis is defined by the cross product between the x- and y-vectors specified on the command line.

The valid queries to an elastomeric bearing element when creating an ElementRecorder object are 'force,' 'localForce,' 'basicForce,' 'localDisplacement,' 'basicDisplacement' and 'material $matNum matArg1 matArg2 ...' Where $matNum is the number associated with the material whose data is to be output.


EXAMPLES:

element elastomericBearing 1 1 2 20.0 2.50 0.02 -P 1 -Mz 2; # for a 2D elastomeric bearing

element elastomericBearing 1 1 2 20 2.50 0.02 -P 1 -T 2 -My 3 -Mz 4; # for a 3D elastomeric bearing



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