Please guide me on which points Gauss quadrature is applied

[compmech]

Hello:

I am doing non linear fea anaylsis and I wirte my own codes instead of using any software. I am kind of lost in numerically integrating a 1D problem.
I want to know that out of the following parameters how many parameters we evaluate at the quadrature points and how many at the nodes.
Shape functions N
Jacobian J
Mass matrix M
Internal force Fint.

Please help me out on this.

Thank you
COmp mech

 

[MToft]

Hi,
You might find this answered better in textbooks eg Huebner & Thornton, or just Googling for lecture notes that go through the detail.

On the other hand, it's simpler just to evaluate everything at Gauss points for consistency. Some smarter codes I think evaluate M and Fint at the nodes...

Might be worth checking some code in a few free-source solvers to see what they do. What sort of non-linearity are you handling: material, contact etc?

It's been a LONG time since I wrote my own code - good luck!
MToft

 

[compmech]

Hi MToft:

Thanks a lot for your suggestions, I went through some text books and figured out different cases. Currently I am dealing with material non linearity.

CompMech