Please help us to resolve the error!!

[Kodai]

Nice to meet you. I am a student studying earthquake engineering at university.


When I run an analysis with OpenSees, the following error occurs and the process stops midway.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
OpenSees -- Open System For Earthquake Engineering Simulation
Pacific Earthquake Engineering Research Center
Version 3.5.0 64-Bit

(c) Copyright 1999-2016 The Regents of the University of California
All Rights Reserved
(Copyright and Disclaimer @ http://www.berkeley.edu/OpenSees/copyright.html)


Model Built
WARNING BandSPDLinLapackSolver::solve() -factorization failed, matrix singular U(i,i) = 0, i= 20
WARNING NewtonRaphson::solveCurrentStep() -the LinearSysOfEqn failed in solve()
StaticAnalysis::analyze() - the Algorithm failed at step: 0 with domain at load factor 1
OpenSees > analyze failed, returned: -3 error flag
SeismicWave-1-drift.out
SeismicWave-1-axial.out
WARNING BandGenLinLapackSolver::solve() -factorization failed, matrix singular U(i,i) = 0, i= 20
WARNING ModifiedNewton::solveCurrentStep() -the LinearSysOfEqn failed in solve()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.002
OpenSees > analyze failed, returned: -3 error flag
WARNING BandGenLinLapackSolver::solve() -factorization failed, matrix singular U(i,i) = 0, i= 20
WARNING ModifiedNewton::solveCurrentStep() -the LinearSysOfEqn failed in solve()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.002
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING BandGenLinLapackSolver::solve() -factorization failed, matrix singular U(i,i) = 0, i= 20
WARNING NewtonRaphson::solveCurrentStep() -the LinearSysOfEqn failed in solve()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.002
OpenSees > analyze failed, returned: -3 error flag
Trying Broyden ..
WARNING BandGenLinLapackSolver::solve() -factorization failed, matrix singular U(i,i) = 0, i= 20
WARNING Broyden::solveCurrentStep() -the LinearSysOfEqn failed in solve()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.002
OpenSees > analyze failed, returned: -3 error flag
Trying NewtonWithLineSearch ..
WARNING BandGenLinLapackSolver::solve() -factorization failed, matrix singular U(i,i) = 0, i= 20
WARNING NewtonLineSearch::solveCurrentStep() -the LinearSysOfEqn failed in solve()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 0.002
OpenSees > analyze failed, returned: -3 error flag
Ground Motion Done. End Time: 0.000000

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I can't pinpoint what's causing it, and I don't know what to fix. If we know the file that is causing the issue, we may be able to provide more details.


If anyone knows or has experienced a similar error, please help me.

[mhscott]

Check your boundary conditions and nodal fixities. You have a rigid body mode in your model.

https://portwooddigital.com/2021/09/12/ ... -to-solve/