RigidDiaphragm command: Difference between revisions

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{|  
{|  
| style="background:yellow; color:black; width:800px" | '''rigidDiaphragm $perpDirn $rNodeTag $cNodeTag1 $cNodeTag2 ...'''
| style="background:yellow; color:black; width:800px" | '''rigidDiaphragm $direction $rNodeTag $cNodeTag1 $cNodeTag2 ...'''
|}
|}


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{|
{|
|  style="width:150px" | '''$perpDirn ''' || direction perpendicular to the rigid plane (i.e. direction 3 corresponds to the 1-2 plane)
|  style="width:150px" | '''$direction ''' || 3D models - direction perpendicular to the rigid plane, e.g., direction 3 (Z) corresponds to the 1-2 (X-Y) plane; 2D models - direction of diaphragm motion, e.g., direction 1 (X) corresponds to motion constrained in the X direction
|-
|-
|  '''$rNodeTag ''' ||  integer tag identifying the retained node
|  '''$rNodeTag ''' ||  integer tag identifying the retained node
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NOTE: The constraint object is constructed assuming small rotations.
NOTE: The constraint object is constructed assuming small rotations for 3D models.


NOTE: The rigidDiaphragm command works only for problems in three dimensions with six-degrees-of-freedom at the nodes (ndf = 6).


EXAMPLE:


EXAMPLE:
3D:


rigidDiaphragm 2 2 4 5 6; constrain nodes 4,5,6 to move as if in the same x-z plane as node 2.
rigidDiaphragm 2 2 4 5 6; constrain nodes 4,5,6 to move as if in the same X-Z plane as node 2


2D:


rigidDiaphragm 1 5 1 3 4 7; constrain nodes 1,3,4,7 to have the same X displacement as node 5


Code Developed by: <span style="color:blue"> fmk </span>
Code Developed by: <span style="color:blue"> fmk </span>

Latest revision as of 15:04, 25 August 2022




This command is used to construct a number of Multi-Point Constraint (MP_Constraint) objects. These objects will constrain certain degrees-of-freedom at the listed constrained nodes to move as if in a rigid plane with the retained node.

rigidDiaphragm $direction $rNodeTag $cNodeTag1 $cNodeTag2 ...

$direction 3D models - direction perpendicular to the rigid plane, e.g., direction 3 (Z) corresponds to the 1-2 (X-Y) plane; 2D models - direction of diaphragm motion, e.g., direction 1 (X) corresponds to motion constrained in the X direction
$rNodeTag integer tag identifying the retained node
$cNodeTag1 $cNodeTag2 ... integer tags identifying the constrained nodes


NOTE: The constraint object is constructed assuming small rotations for 3D models.


EXAMPLE:

3D:

rigidDiaphragm 2 2 4 5 6; constrain nodes 4,5,6 to move as if in the same X-Z plane as node 2

2D:

rigidDiaphragm 1 5 1 3 4 7; constrain nodes 1,3,4,7 to have the same X displacement as node 5

Code Developed by: fmk