3D RC Frame convergence problem

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parkm
Posts: 17
Joined: Mon Jun 04, 2012 11:14 am
Location: Urmia university

3D RC Frame convergence problem

Post by parkm »

Hello all,
I have to analysis my 3D RC frame in bidirectional Uniform Earthquake ground motion.
for scalefactor >0.5 the convergence fail appears.
Dt Analysis is 0.005
smaller Dt Analysis didn't work.
I have to analysis my model in scale factor =1.0 and 2.0.
I appreciate any comments to solve my problem.
baozai
Posts: 212
Joined: Tue Jan 04, 2011 3:39 am
Location: Southeast University

Re: 3D RC Frame convergence problem

Post by baozai »

I think Maybe you can change the algorithm, from the dynamic analysis I did(only one-directional uniform dynamic analysis), I think Krylov-Newton and Broyden are easier for the convergence, the use of UmfPack in system command is also helpful if your model is large. small change in your material (elastic modulus and strength) and fiber section maybe also helpful. I don't know whether it is useful...
Baozai
parkm
Posts: 17
Joined: Mon Jun 04, 2012 11:14 am
Location: Urmia university

Re: 3D RC Frame convergence problem

Post by parkm »

thanks, it worked!
parkm
Posts: 17
Joined: Mon Jun 04, 2012 11:14 am
Location: Urmia university

Re: 3D RC Frame convergence problem

Post by parkm »

Dear all,
i have used concrete02, when i use concrete07 there is fail as following, could you please help me what is wrong?
Starting OpenSees..


OpenSees -- Open System For Earthquake Engineering Simulation
Pacific Earthquake Engineering Research Center -- 2.2.2

(c) Copyright 1999,2000 The Regents of the University of California
All Rights Reserved
(Copyright and Disclaimer @ http://www.berkeley.edu/OpenSees/copyright.html)


WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 2
WARNING NewtonRaphson::solveCurrentStep() -the LinearSysOfEqn failed in solve()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 0.1
OpenSees > analyze failed, returned: -3 error flag
Model Built
=========================
Dynamic Analysis Starting
=========================
SF = 1.0 1.0
Tx = 0.27720245268885163 sec
Ty = 0.26628324401967907 sec
WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 2
WARNING ModifiedNewton::solveCurrentStep() -the LinearSysOfEqn failed in solve()

DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.01
OpenSees > analyze failed, returned: -3 error flag
WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 2
WARNING ModifiedNewton::solveCurrentStep() -the LinearSysOfEqn failed in solve()

DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.01
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 2
WARNING NewtonRaphson::solveCurrentStep() -the LinearSysOfEqn failed in solve()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.01
OpenSees > analyze failed, returned: -3 error flag
Trying Broyden ..
WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 2
WARNING Broyden::solveCurrentStep() -the LinearSysOfEqn failed in solve()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.01
OpenSees > analyze failed, returned: -3 error flag
Trying NewtonWithLineSearch ..
WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 2
WARNING NewtonLineSearch::solveCurrentStep() -the LinearSysOfEqn failed in solve
()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.01
OpenSees > analyze failed, returned: -3 error flag
Dynamic Analysis Finished
=========================
Ground Motion Done. End Time: 0.005000
---------------------------------------------------------------------------
End of script <C:\tcleditor\bin\Challenge\Opensees> reached, Press any key to co
ntinue
parkm
Posts: 17
Joined: Mon Jun 04, 2012 11:14 am
Location: Urmia university

Re: 3D RC Frame convergence problem

Post by parkm »

I found out the problem!!
tnx :)
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