Q:

How to check the PSI convergence criteria?

 

R:

Force convergence should be used as the primary convergence criteria. As an example, one might use the default values to start with for all the three (displacement/rotation/force) and then tweak the deflection tolerances as required. Longer piles or softer soils may need larger deflection tolerances. When serviceability is important, deflection criteria should be stricter. Force convergence tolerance should not be relaxed. 

Of course, to make sure that user is using sufficient convergence tolerances, one would carry out repeated analyses to make sure that the results that they are interested in (e.g. internal forces) do not change much. The 'right' tolerances are best left to engineering judgement, which is why it is a user-defined input in SACS.

One should not compare Pin support reaction at pile head with actual pile head.