Error using Brick Element

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Michaelson
Posts: 28
Joined: Sat Jan 13, 2018 8:34 pm
Location: Shanghai Jiao Tong University

Error using Brick Element

Post by Michaelson » Wed Dec 12, 2018 2:29 am

hello everyone,
I am trying to use stdbrick element to model a cocncrete wall (can I ?) , but I am getting following errors even for a small model
WARNING FE_Element::setID() - numDOF and number of dof at the DOF_Groups
WARNING FE_Element::setID() - numDOF and number of dof at the DOF_Groups
WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 1
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
-3

model:

model basic -ndm 3 -ndf 6
#Define geometry of Concrete
node 1 0.3 0.3 0
node 2 0 0.3 0
node 3 0 0 0
node 4 0.3 0 0
node 5 0.3 0.3 0.3
node 6 0 0.3 0.3
node 7 0 0 0.3
node 8 0.3 0 0.3

#Boundary conditions
fix 1 0 0 1 0 0 0
fix 2 0 0 1 0 0 0
fix 3 1 1 1 0 0 0
fix 4 0 1 1 0 0 0

nDMaterial ElasticIsotropic 1 30000000 0.2 24

element stdBrick 1 1 2 3 4 5 6 7 8 1

set load 1

pattern Plain 1 Linear {
load 5 0 0 -$load 0 0 0
load 6 0 0 -$load 0 0 0
load 7 0 0 -$load 0 0 0
load 8 0 0 -$load 0 0 0
}

constraints Plain
numberer RCM
system BandGeneral
test RelativeNormUnbalance 1.0e-6 20 1;
algorithm Newton;
integrator LoadControl 0.1
analysis Static

recorder Element -file Brickstress.out -time -ele 1 stresses
recorder Element -file Brickstrain.out -time -ele 1 strains
analyze 10

Thanks in advance :)

Michaelson
Posts: 28
Joined: Sat Jan 13, 2018 8:34 pm
Location: Shanghai Jiao Tong University

Re: Error using Brick Element

Post by Michaelson » Wed Dec 12, 2018 2:34 am

units are KN,m
I tried for even 0.001KN load, but fails :(

Michaelson
Posts: 28
Joined: Sat Jan 13, 2018 8:34 pm
Location: Shanghai Jiao Tong University

Re: Error using Brick Element

Post by Michaelson » Wed Dec 12, 2018 9:07 pm

seems like stdbrick element should not be defined with -ndm 3 -ndf 6 :?
when I define it with -ndm 3 -ndf 3 , its works just fine :!:
But I need -ndf 6 for my analysis as I am supposed to use a shell element which cannot be defined with -ndf 3. what should I do ??
please help :(

Michaelson
Posts: 28
Joined: Sat Jan 13, 2018 8:34 pm
Location: Shanghai Jiao Tong University

Re: Error using Brick Element

Post by Michaelson » Thu Dec 13, 2018 11:24 pm

apparently, you could define more than one model builder . Did not know that, sorry to bother :oops:

zemiki
Posts: 13
Joined: Tue Jan 16, 2018 9:38 pm
Location: South Korea

Re: Error using Brick Element

Post by zemiki » Thu Feb 13, 2020 6:21 am

I defined my structure with model builder of -ndm 3 -ndf6 and my soil as -ndm 3 -ndf 3 with brick element. I connected the base of the structure with the brick elements with eqdof in dof1 and dof2. my analysis failed even for gravity load. Michael midezutd@gmail.com

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