Pushover analysis

Libra23 · Post by **Libra23** » Sat Apr 14, 2007 12:12 am

after running eigen analyis I started with gravity but it gives me this problem :

WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 178
WARNING NewtonRaphson::solveCurrentStep() -the LinearSysOfEqn failed in solve()
StaticAnalysis::analyze() -the algorithm failed at iteration :0 with domain at load factor 0.2
analyze failed,returned -3 error flag

so I have also problems with pushover analysis,
if I send you my file colud you look at it?
Thanks

silvia · Post by **silvia** » Sat Apr 14, 2007 7:31 am

it's a good sign, you have convergence problems.
you need to change something about the analysis at this point.
please look at the examples manual, maybe example 5 or so, it has the script you want.

Libra23 · Post by **Libra23** » Sat Apr 14, 2007 8:25 am

I took script from example manual and get that problem,this is the script I use:

# Gravity-analysis parameters -- load-controlled static analysis
set Tol 1.0e-8; # convergence tolerance for test
variable constraintsTypeGravity Plain; # default;
if { [info exists RigidDiaphragm] == 1} {
if {$RigidDiaphragm=="ON"} {
variable constraintsTypeGravity Lagrange; # large model: try Transformation
}; # if rigid diaphragm is on
}; # if rigid diaphragm exists
constraints $constraintsTypeGravity ; # how it handles boundary conditions
numberer RCM; # renumber dof's to minimize band-width (optimization), if you want to
system BandGeneral ; # how to store and solve the system of equations in the analysis (large model: try UmfPack)
test EnergyIncr $Tol 6 ; # determine if convergence has been achieved at the end of an iteration step
algorithm Newton; # use Newton's solution algorithm: updates tangent stiffness at every iteration
set NstepGravity 10; # apply gravity in 10 steps
set DGravity [expr 1./$NstepGravity]; # first load increment;
integrator LoadControl $DGravity; # determine the next time step for an analysis
analysis Static; # define type of analysis static or transient
analyze $NstepGravity; # apply gravity

What do you suggest to change?I tried something but get the same!
Thanks

silvia · Post by **silvia** » Sat Apr 14, 2007 8:38 am

no. that one is for gravity, right?
you want to do the pushover.

Libra23 · Post by **Libra23** » Sat Apr 14, 2007 9:06 am

Yes I have to do pushover but the problem I get:

Code: Select all

WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 178 
WARNING NewtonRaphson::solveCurrentStep() -the LinearSysOfEqn failed in solve() 
StaticAnalysis::analyze() -the algorithm failed at iteration :0 with domain at load factor 0.2 
analyze failed,returned -3 error flag

is about gravity analysis and then the same for each step of pushover!

I don't know what's wrong!

Libra23 · Post by **Libra23** » Sat Apr 14, 2007 9:08 am

For pushover I use script of example 8.

Libra23 · Post by **Libra23** » Mon Apr 16, 2007 5:32 am

I need help!
Thanks

silvia · Post by **silvia** » Mon Apr 16, 2007 7:32 am

the pushover script in example 8 should help.

Libra23 · Post by **Libra23** » Tue Apr 17, 2007 10:38 am

I looked at it,maybe it could be a model problem...if you remember I have modeled walls as non linear beam column elements with large section ,at the edge of section I had two nodes ( 0 )that are connected with nothing...someone suggests me to use beam with elastic section to connect them ( 0 ) with node ( X ) of non linear beamColumn that represent the wall.
I mean :

0-------X--------0

it doens't work the same!
What do you think about it?

silvia · Post by **silvia** » Tue Apr 17, 2007 11:23 am

i am a bit confused, you might want to discuss this with someone who is physically near you, as it is a modelling issue.

Libra23 · Post by **Libra23** » Tue Apr 17, 2007 11:40 am

You are right....it's a pity that nobody near me can't use this program and is able to help!
Thanks the same,really, I believe I must help myself!

Libra23 · Post by **Libra23** » Tue Apr 17, 2007 12:13 pm

I have read in the manual that ,using eleLoad command ,nonlinearBeamColumn might have problems converging .... could it be this that gives me problems in my model?

silvia · Post by **silvia** » Tue Apr 17, 2007 1:40 pm

nope.

Libra23 · Post by **Libra23** » Wed Apr 18, 2007 6:22 am

in examples 8 of manual if I want to run pushover do I open example about pushover and call within it example that defines model?

silvia · Post by **silvia** » Wed Apr 18, 2007 8:20 am

first you source the build file,
then you source the analysis file