failed to converge after 1500 iteration

[alimohammadian]

Hello

I model 12 story frame. I try Time history analysis but after 17 sec (failed to converge after 1500 iteration current norm). Several times I check my code but I could not find the problem.

Please guide me.

The following code has been placed
download link:
http://www.uploadmb.com/dw.php?id=1455259248

[fmk]

if the 1500 is with regular Newton, don't waste your time, 10 is more than enough.
if it fails with 10 switch to ModifiedNewton -initial

if you want to ensure it does not fail don't do nonlinear analysis!

[alimohammadian]

dear fmk

my Analysis codes are:

numberer Plain
system BandGeneral
test NormDispIncr 1.0e-5 1500 2;
algorithm KrylovNewton
integrator Newmark 0.5 0.25
analysis Transient
analyze [expr int(62.82/$dt)] $dt


Is it better to use EnergyIncr insted of NormDispIncr ?
if yes How to put its parameters؟