degree of freedom

Stacking of DOFs in Abaqus

Submitted by knutankv on Wed, 03/06/2013 - 15:05

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I am studying the response of a bridge in MATLAB, and have successfully retrieved mass and stiffness matrices from Abaqus using the following keywords:

*Step

*Matrix generate, STIFFNESS, MASS

*Matrix output, STIFFNESS, MASS, FORMAT=COORDINATE

*End step

This gives matrices on a mathematical form, very well suited for use with MATLAB.

DOFs in Abaqus

Submitted by salingerv on Fri, 11/23/2012 - 15:53

Hi,

I got a simple 2D problem (a rectangular shell, static general, CPS4R element), with 557 nodes, each of them have 2 DOFs (U1 and U2), according to the data file. But when I print out the ELEMENT STIFFNESS MATRIX, for each element it is a 12x12 matrix which means the rotational DOF about z axis is also taken into account. How can I omit this 3rd DOF? Can I?

Thank you.

Help me : Node Print of User Defined Degree of Freedom

Submitted by somusshabadi on Sat, 09/15/2012 - 15:36

Hello Experts,

I have written a uel subroutine where I have totally 12 degree of freedom. Among these 12 degree of freedom, 6 are standard abaqus degree of freedom (3 Displacements and 3 Rotations) and another 6 are User defined degree of freedom.

I assign these these degree of freedom in following way.

*USER ELEMENT,TYPE =U9, NODES=9,PROPERTIES=24,coordinates=3

1,2,3,4,5,6

9,1,2,3,4,5,6,7,8,9,10,11,12