Pro/Mechanica - Bolted Connection

I am running an analysis that contains a bolted connection in shear
and tension. I am interested in the area around the bolt so I have
used a solid model of the bolt and contact regions between the mating
faces of the components being clamped. A bolt pre-load is applied
using a transversely isotropic material and a global temperature load.
I have run the analysis and need to check that the temperature gives
the correct pre-load.

How do I determine the tension force in the solid bolt model?

Also, should I have a contact region between the bolt head and
component to allow it to slip (bolt is in shear and tension)?

Any help would be greatly appreciated.

Cheers

Martin

 

Bolt Loading can get complicated depending upon if you wish to consider
friction and slip within the threads.
If you aren't interested in this then it is fairly straightforward, and you
can use basic Elastic stress-strain principles.
Ie
E = stress/strain

As you know strain is a relationship between original length and change in
length, which you have from your change in temp.
You know the Young's Modulus (E) and the X-Sect area of the bolt thread
(this should be the id of thread pitch).
So you should be able to transpose the above equation for Force (pre-load).

You would generally work to within 70-80% of material Yield (0.2% Proof
Stress) to define the pre-load and ultimately the required bolt torque.

I hope this is of use.

Cheers