ZeroLengthContactNTS2D: Difference between revisions

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| '''$sNdNum''' || Number of Slave Nodes
| '''$sNdNum''' || Number of Slave Nodes
|-
|-
| '''$matTag1 $matTag2 ...''' || tags associated with previously-defined UniaxialMaterials
| '''$mNdNum''' || Number of Master nodes 
|-
|-
| '''$dir1 $dir2 ...''' || material directions:
| '''$Nodes ...''' || Slave and master node tags respectively
 
|-
1,2,3 - translation along local x,y,z axes, respectively
| '''$Kn''' || Penalty in normal direction
 
4,5,6 - rotation about local x,y,z axes, respectively
|-
|-
| '''$x1 $x2 $x3''' || vector components in global coordinates defining local x-axis (optional)
| '''$Kt''' || Penalty in tangential direction
|-
|-
| '''$yp1 $yp2 $yp3''' || vector components in global coordinates defining vector yp which lies in the local x-y plane for the element. (optional)
| '''$phi''' || Friction angle in degrees
|}
|}


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# The contact element is node-to-segment (NTS) contact. The relation follows Mohr-Coulomb frictional law: <math>T = N tan(\phi)</math>, where T is the tangential force, N is normal force across the interface and ,math>\phi</math> is friction angle.
# The contact element is node-to-segment (NTS) contact. The relation follows Mohr-Coulomb frictional law: <math>T = N tan(\phi)</math>, where T is the tangential force, N is normal force across the interface and ,math>\phi</math> is friction angle.
# For 2D
# For 2D contact, slave nodes and master nodes must be 2 DOF and notice that the slave and master nodes must be entered in counterclockwise order.
 
# The resulting tangent from the contact element is non-symmetric. Switch to the non-symmetric matrix solver if convergence problem is experienced.
# As opposed to node-to-node contact, predefined normal vector for node-to-segment (NTS) element is not required because contact normal will be calculated automatically at each step.
# contact element is implemented to handle large deformations.


EXAMPLE:
EXAMPLE:

Revision as of 22:09, 21 January 2010

This command is used to construct a zeroLengthContactNTS2D element object. This is a Node-To-Segment (NTS) frictional contact element used in two dimensional analysis for contact between elements with 2 DOF nodes.

element zeroLengtContactNTS2Dh $eleTag -sNdNum $sNdNum -mNdNum $mNdNum -Nodes $Nodes $Kn $kt $phi




$eleTag unique element object tag
$sNdNum Number of Slave Nodes
$mNdNum Number of Master nodes
$Nodes ... Slave and master node tags respectively
$Kn Penalty in normal direction
$Kt Penalty in tangential direction
$phi Friction angle in degrees

NOTES:

  1. The contact element is node-to-segment (NTS) contact. The relation follows Mohr-Coulomb frictional law: <math>T = N tan(\phi)</math>, where T is the tangential force, N is normal force across the interface and ,math>\phi</math> is friction angle.
  2. For 2D contact, slave nodes and master nodes must be 2 DOF and notice that the slave and master nodes must be entered in counterclockwise order.
  3. The resulting tangent from the contact element is non-symmetric. Switch to the non-symmetric matrix solver if convergence problem is experienced.
  4. As opposed to node-to-node contact, predefined normal vector for node-to-segment (NTS) element is not required because contact normal will be calculated automatically at each step.
  5. contact element is implemented to handle large deformations.

EXAMPLE:

element zeroLengthContactNTS2D 1 -sNdNum 6 -mNdNum 6 - Nodes 5 10 12 3 9 11 1 4 2 8 7 1e8 1e8 16

Example 1:

Example 2:

REFERENCES:



Code Developed by: R.G. Mikola, UC Berkeley and N. Sitar, UC Berkeley