*OPT_CONV

Data format :

A single line with one parameter.

IOP

Status :

Optional

Purpose :

To apply convergence criteria and/or maximum displacements in iteration within each group of elements / rigid bodies (so called local option as opposed to the global option where the reference is the whole model).

Details :

Parameter	Description
IOP	IOP = 1 : Convergence criteria and displacements increments are local IOP = 2 : Convergence criteria is global and displacements increments is local IOP = 3 : Convergence criteria is local and displacements increments is global

Note

Convergence criteria / maximum displacement used to be checked for the whole set of elements at once based on the maximum internal loads among all elements / element length. This could yield some accuracy issues when the analysis included very taut lines AND other lines experiencing almost zero loads.

Convergence / displacement can now be checked separately for eachgroup of elements and rigid bodies. This feature may be activated through the *OPT_CONV keyword.

The solution method however still considers the complete set of elements as a whole (complete matrix inversion)