thank you for your reply! I am aware of the much easier ways to model preloaded bolts. However, for my research it is essential to model the application of the preload as exact as possible. For example, it is important for me to consider the torsional stresses resulting of the friction in the thread. Furthermore I am looking at very high over-elastic preload levels beyond necking. Therefore, the simple application of a preload force by the in-built tool would be unrewarding in my case.
Do you have any idea what I could try to improve my results using my current approach?
Thank you again and best regards