Non convergence of non linear problem

[formosa.darrell4]

Hi, 

I am a Structural Engineering university student, and our design project is to design a Cable stayed bridge. I am modeling the bridge on Robot and once i set the cable members as cables the program gives me the error of Non-convergence of non linear problem, this is with the Super imposed dead load and when I set a moving load. Ive tried to change the setting as per the Autodesk solutions but none seem to work. Does anyone know what the problem might be?
I have attached the robot file below.

thanks 

Darrell  

[Krzysztof_Wasik]

Hi @formosa.darrell4 

You have used incorrect format for model saving. Use RTD format  (not STP)

[formosa.darrell4]

for some reason it does not allow me to upload the .rtd file 

[Romanich]

Hi @formosa.darrell4 ,

Zip the model first or if the size of the model is big use WeTransfer for example.

[formosa.darrell4]

this is it

[Krzysztof_Wasik]

Hi @formosa.darrell4 

It seems that cable initial forces proportion is not correct (cannot be balanced in the model)

Increase force in cable 300 mm to 210 kN

Activate Matrix update after each iteration (for each load case)

[Stephane.kapetanovic]

Hi @formosa.darrell4 

Two small things. The bridge deck does not have a correctly defined section (Ax, Ay, Ix null), use the section creation tool for this. You must also remove the self weight of the cables by limiting the elements to a part of the structure equal to the bars 19A23 only because the cables do not have to be loaded.

Best regards