How to use connectors in a model which contains parts with initial stress (predefined field) 1

[Emre SENGUL]

I have a model which contains some parts having initial stress. I defined this initial stress by using predefined field feature. However, I took an error 'Initial conditions specified on 1 elements are illegal for those elements. The elements have been identified in element set ErrElemBadInitCond.' when I tried to run my model. Also I took this error 'INITIAL STRESSES MAY NOT BE APPLIED TO CONNECTPR ELEMENTS. USE A NONLINEAR *CONNECTOR ELASTICITY DEFINITION INSTEAD' although my connector sections are tabulated nonlinear values. How can I use my connector parts within this model?

 

[FEA way]

Apparently you applied this initial stress to one of the connectors. Make sure that these parts of the model are not included in predefined field definition.

 

[Emre SENGUL]

I understood. So, could the nodes which I defined predefined field conflict the nodes of connectors? Could such a case cause to confuse the model about assigning initial stress?

 

[FEA way]

Initial stresses are always applied to elements, not nodes. Just remove any connector wires from the set used for predefined field definition if they are included there.

 

[Emre SENGUL]

Without connectors my model run properly. While I defining predefined field, I am picking just related elements not connectors. However, I noticed that initial stress is defined for the first parts (alphabetically) in my model regardless of my picked set. Could independent meshing for the parts in my model cause this situation? So, initial stress may be applied on wire/connector elements first. Is this possible?

 

[FEA way]

You can try this but another way is to open generated input file and delete connector wire from element set specified in initial stress definition.

 

[Emre SENGUL]

I don't know actually where element set for initial stress definition in input file is given but I will try this.

 

[FEA way]

Find keyword for initial condition (*Initial conditions, type=stress) and there you will see a reference to element set. This set will be defined separately in the input file.

 

[Emre SENGUL]

Actually, my model read initial stress from a .odb file and this file is generated from another model which includes just related two parts (without any connectors). so, it is like below in the input file and there is no any set near this part.

** Name: IC-1 Type: Stress
*Initial Conditions, type=STRESS, file=C:/temp/.......odb, step=2, inc=17

 

[Emre SENGUL]

There is a new situation about this case. Although a simple model with initial stress and connectors give results in Abaqus 2017 without any error, the same model in Abaqus 2019 ended with an error which I mentioned before. Do you have any idea about the reason of this situation?

 

[Emre SENGUL]

Interestingly, I solved my problem which I mentioned before by using previous version of Abaqus.