thermal load in structural elements

[M. Kurdi]

Hello,
I am interested in applying steady thermal loads to frame elements. Initially I thought of using a user element to apply the thermal load and build stress stiffness matrix. However the material properties of the frame elements (ex. area, modulus, etc.) are not available to the user element subroutine. Or is there a better way to augment this load to existing elements? Also I didn't see an isw task for building the geometric stiffness matrix in the user element. How can one transfer this matrix for eigenvalue analysis.
Thanks for your help.

[Prof. R.L. Taylor]

Applying the themal load does require coding in some form.  You may want to add the computation to the elelment you plan to use.

The geometric stiffness is computed under isw=5 for imtyp=2 (imtyp = 1 is for masses).  The value for imtyp is set when you specify either 'mass' or 'geom' (see pmacr1.f for details)