while modelling a simple calculation for a pretensioned bolt with 1D elements, i got the following problem:
In the visualisation you can see, that the 1D element on which the pretension is applied to gets lengthen. (A 'pretension' is applied, but to the wrong direction.)
According to the pretension file (.pret) everything seems to be reasonable, even if i add an additional tension load case after the pretension sub. However the contact forces do not.
The '1D bolt' i used is a single ROD element , which is connect to the guiding (independent) node of a RBE2 spider of the washer (shell elements) to both sides. I attached a picture where you can see my definition in the Pretension Manager window. I also attached a picture of the property of the ROD element.
I read all the infos in the users guide and online-help, but can't find an answer to my question. How can this problem be solved? Do i have to use a special orientation of the pretension section and how is this defined correctly.
Please, i need your help!