ZeroLength Element: Difference between revisions

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| style="background:yellow; color:black; width:800px" | '''element zeroLength $eleTag $iNode $jNode -mat $matTag1 $matTag2 ... -dir $dir1 $dir2 ... <-orient $x1 $x2 $x3 $yp1 $yp2 $yp3> <-doRayleigh $rFlag>'''
| style="background:lime; color:black; width:800px" | '''element zeroLength $eleTag $iNode $jNode -mat $matTag1 $matTag2 ... -dir $dir1 $dir2 ...<-doRayleigh $rFlag> <-orient $x1 $x2 $x3 $yp1 $yp2 $yp3>'''
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| '''$dir1 $dir2 ...''' || material directions:
| '''$dir1 $dir2 ...''' || material directions:
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| || if in 2D: 1,2 - translation along local x,y axes; 3  -  corresponds to rotation
|-   
|-   
| || if in 3D: 1,2,3 - translation along local x,y,z axes, respectively; 4,5,6 - rotation about local x,y,z axes, respectively
| || 1,2,3 - translation along local x,y,z axes, respectively;
|- 
| || 4,5,6 - rotation about local x,y,z axes, respectively
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|-
| '''$x1 $x2 $x3''' || vector components in global coordinates defining local x-axis (optional)
| '''$x1 $x2 $x3''' || vector components in global coordinates defining local x-axis (optional)
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If the 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 vectors x and yp vectors specified on the command line.
If the 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 vectors x and yp vectors specified on the command line.


The valid queries to a zero-length element when creating an ElementRecorder object are 'force,' 'deformation,' 'stiff,' and 'material $matNum matArg1 matArg2 ...' Where $matNum is the tag associated with the material whose data is to be output.
The valid queries to a zero-length element when creating an ElementRecorder object are 'force,' 'deformation,' and 'material $i matArg1 matArg2 ...' Where $i is an integer indicating which of the materials whose data is to be output (a 1 corresponds to $matTag1, a 2 to $matTag2, and so on).  
 
 
 
EXAMPLE:
EXAMPLE:


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element zeroLength 1 1 2 -mat 1 -dir 1 -orient 1 1 0 -1 1 0; # truss tag 1 between nodes 1 and 2 acting in local direction 1 defined with material 1. Local direction 1 attains 45 degrees with global X axis
element zeroLength 1 1 2 -mat 1 -dir 1 -orient 1 1 0 -1 1 0; # truss tag 1 between nodes 1 and 2 acting in local direction 1 defined with material 1. Local direction 1 attains 45 degrees with global X axis
element zeroLength 1 1 2 -mat 1 -dir 1 -doRayleigh 1 -orient 1 1 0 -1 1 0; # the same as the example above but also includes the stiffness of this element in calculation of the damping matrix if Rayleigh command is invoked later.


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Code Developed by: <span style="color:blue"> Gregory L. Fenves, University of Texas, Austin. </span>
Code Developed by: <span style="color:blue"> Gregory L. Fenves, University of Texas, Austin. </span>

Latest revision as of 16:01, 3 October 2014



This command is used to construct a zeroLength element object, which is defined by two nodes at the same location. The nodes are connected by multiple UniaxialMaterial objects to represent the force-deformation relationship for the element.

element zeroLength $eleTag $iNode $jNode -mat $matTag1 $matTag2 ... -dir $dir1 $dir2 ...<-doRayleigh $rFlag> <-orient $x1 $x2 $x3 $yp1 $yp2 $yp3>



$eleTag unique element object tag
$iNode $jNode end nodes
$matTag1 $matTag2 ... tags associated with previously-defined UniaxialMaterials
$dir1 $dir2 ... material directions:
1,2,3 - translation along local x,y,z axes, respectively;
4,5,6 - rotation about local x,y,z axes, respectively
$x1 $x2 $x3 vector components in global coordinates defining local x-axis (optional)
$yp1 $yp2 $yp3 vector components in global coordinates defining vector yp which lies in the local x-y plane for the element. (optional)
$rFlag optional, default = 0
rFlag = 0 NO RAYLEIGH DAMPING (default)
rFlag = 1 include rayleigh damping

NOTE:

If the 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 vectors x and yp vectors specified on the command line.

The valid queries to a zero-length element when creating an ElementRecorder object are 'force,' 'deformation,' and 'material $i matArg1 matArg2 ...' Where $i is an integer indicating which of the materials whose data is to be output (a 1 corresponds to $matTag1, a 2 to $matTag2, and so on). EXAMPLE:

element zeroLength 1 2 4 -mat 5 6 -dir 1 2; # truss tag 1 between nodes 2 and 4 acting in directions 1 and 2 with materials 5 and 6 respectively.

element zeroLength 1 1 2 -mat 1 -dir 1 -orient 1 1 0 -1 1 0; # truss tag 1 between nodes 1 and 2 acting in local direction 1 defined with material 1. Local direction 1 attains 45 degrees with global X axis

element zeroLength 1 1 2 -mat 1 -dir 1 -doRayleigh 1 -orient 1 1 0 -1 1 0; # the same as the example above but also includes the stiffness of this element in calculation of the damping matrix if Rayleigh command is invoked later.

Code Developed by: Gregory L. Fenves, University of Texas, Austin.

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