hi prof. McKenna
I have one question please, I appreciate your help.
my model consist a plane 2D frame. I modeled beam and column by displacement based nonlinear element and so I sliced each element to several sub-element. (because convergence problem I can not use other type of nonlinear element).
I want to obtain the rotation at ends of elements. I tried several manner but I am so confused. I am hopping that you could help me.
1- use of basicDeformation recorde:
recorder Element -file $dataDir -time -ele 1 basicDeformation;
this command takes one element ID number and gives two end rotations. but since I used disp based nonlinear element and I sliced one element to several element I can't use this command.
2- use of node disp coomand:
recorder Node -file nodedisp.out -time -node 1 -dof 3 disp
I have a question from this command.
2-1- can I use this recorder to obtain the rotation at ends of element in such 2D planner frame?
2-2- i know that the nodes have global coordinate, but what axis is about this rotation ?
please assume a horizontal beam from node 1 to node2 and a vertical column from node 1 to node 3. (node 1 is in intersection of beam and column) if I use above recorder and obtain the rotation of node 1 equal 0.03 , does it mean both beam and column have a rotation equal 0.03 at their first point?
would you please help me which recorder can i use to obtain the rotation at ends of element?
at the end, I appreciate you.
thank you so much for your advance.
rotation at the end of element
Moderators: silvia, selimgunay, Moderators
Re: rotation at the end of element
1. the end rotations can be found looking at the results from the 2 end elements if you have discretized it .. the rotations are results 2 and 3, result 1 is axial deformation.
2. the rottaions can be calculated, but not just by looking at the nodal rotations, you also have to factor in the element orientaion, nodal displacement and using element length and then addding the node rotations you can determine the end rotations.
3. in 2d the rotation is about the other axis out .. if you consider x axis and y axis as the 2 axis, then the z axis is out of the plane .. axis and rotation follow right hand rule.
2. the rottaions can be calculated, but not just by looking at the nodal rotations, you also have to factor in the element orientaion, nodal displacement and using element length and then addding the node rotations you can determine the end rotations.
3. in 2d the rotation is about the other axis out .. if you consider x axis and y axis as the 2 axis, then the z axis is out of the plane .. axis and rotation follow right hand rule.