Why does analysis not converge for my vertical cable system?
ANSWER: Vertical cables may cause convergence problems when they begin analysis with slack. To resolve such an issue, introduce a load pattern which applies a small tensile force to each cable, perhaps with a strain value of -0.0001. Create a nonlinear static load case which starts from zero and corresponds to this load pattern. Start all other load cases from this prestrain load case, but apply a scale factor of -1 to the prestrain load pattern. This will zero-out the initial tension as other loads are applied, and should improve convergence.
- Cable FAQ – Initial cable conditions