time history analysis failed

[robab]

Hi
How can I solve this problem in time history nonlinear analysis?

OpenSees > analyze failed, returned: -3 error flag
WARNING - ForceBeamColumn2d::update - failed to get compatible element forces & deformations for element: 240(dW: << 487883)
Domain::update - domain failed in update
Newmark::update() - failed to update the domain
WARNING NewtonLineSearch::solveCurrentStep() -the Integrator failed in update()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 3.08
OpenSees > analyze failed, returned: -3 error flag
Dynamic analysis - Failed at 3.080000

thanks

[fmk]

i suggest you look at the simple examples online for what to do in case of failure, try Newton with initial stiffness iterations or something for those steps that the analysis fails.
http://opensees.berkeley.edu/wiki/index ... e_Analysis

if that fails look at the section definitions, the section(s) in that element have been clobbered and are probably returning 0 or neg stiffness. tweaking the sections sometimes works. if that fails try replacing the element with a few disp based elements.