Material fail in gravity load

[majidzar]

Hi,
I have RC frame with two bay and one story with Gravity loading and cycling loading
when I put Gravity loads on the beams(on the bay between columns) an error occur in opensees "Uniaxial material::setTrial<> material fail in setTrialStrian<> Large Trial compressive strain"
This error repeat many time and at the end this error appear: DisplacementControl::update_model fail to update for new dU
WARNING AcceleratedNewton::solveCurrentStep<>_the Integration failed in update
StaticAnalysis::analyze<>-the Algorithm Failed at iteration:0 with domain at load factor 1.79421
analyze failed returned :-3 error flag

But when I put gravity loads exactly on the columns( on the joints ) the error disappear and i get good result.
I divided the beams to 4 element and put the load on the nodes of the beams and also my model have to cantilever beams and I want to put gravity loads on them.

please help me to put the gravity loads on beams.

pattern Plain 1 "Constant" {
load 14 0 -$Py 0 0 0 0
load 16 0 -$Py 0 0 0 0
load 18 0 -$Py 0 0 0 0
load 20 0 -$Py 0 0 0 0
load 22 0 -$Py 0 0 0 0
load 24 0 -$Py 0 0 0 0
}

set GravSteps 10;
integrator LoadControl [expr 1./$GravSteps];
system BandGeneral
test NormDispIncr 1.0e-4 2000 0
constraints Plain
numberer Plain
algorithm KrylovNewton
analysis Static
analyze $GravSteps
loadConst -time 0.0 # keep gravity load and restart time lead to lateral-load analysis
wipeAnalysis


set Px [expr $Weight/8];; # Reference lateral load

#Set lateral load pattern with a Linear TimeSeries
pattern Plain 2 "Linear" {
load 17 $Px 0 0 0 0 0
load 21 $Px 0 0 0 0 0
}

# Define analysis parameters

system BandGeneral
test NormDispIncr 1.0e-4 2000
numberer Plain
constraints Plain
algorithm KrylovNewton
analysis Static


set dU1 0.1
set dU2 -0.1

# Perform the analysis
integrator DisplacementControl 19 1 $dU1
analyze 20
integrator DisplacementControl 19 1 $dU2
analyze 39
integrator DisplacementControl 19 1 $dU1
analyze 39
integrator DisplacementControl 19 1 $dU2
analyze 39
integrator DisplacementControl 19 1 $dU1
analyze 39
integrator DisplacementControl 19 1 $dU2
analyze 39
integrator DisplacementControl 19 1 $dU1
analyze 19
###############################################

Thanks

[majidzar]

any reply??????

[fmk]

this does not belong in this form .. post it in the users forum. this will be deleted tomorrow.