static analysis warning

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pinash
Posts: 5
Joined: Sun Oct 27, 2013 10:08 pm
Location: tehran

static analysis warning

Post by pinash » Sun Oct 27, 2013 11:26 pm

hi,
these is problem in my opensees text. i can not find out how to correct it.

warning BandGenLinLapackSolver::solve <> -LAPACK routine returned 27
warning NewtonRaphson::solveCurrentSteph -the LinearSysOfEqn failed in solve <>
static analysis::<> -the Algorithm failed at iteration: 0 with domain at load factor 0.1
opensees> analyze failed, returned:-3 error flag

pleas guide me

mhscott
Posts: 610
Joined: Tue Jul 06, 2004 3:38 pm
Location: Corvallis, Oregon USA
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Re: static analysis warning

Post by mhscott » Mon Oct 28, 2013 7:37 am

It looks like you have rigid body motion. Check your boundary conditions to make sure RBM is prevented.

pinash
Posts: 5
Joined: Sun Oct 27, 2013 10:08 pm
Location: tehran

Re: static analysis warning

Post by pinash » Mon Oct 28, 2013 10:44 am

mhscott wrote:
> It looks like you have rigid body motion. Check your boundary conditions to
> make sure RBM is prevented.
can you explain what is RBM?

mhscott
Posts: 610
Joined: Tue Jul 06, 2004 3:38 pm
Location: Corvallis, Oregon USA
Contact:

Re: static analysis warning

Post by mhscott » Mon Oct 28, 2013 11:24 am

RBM = rigid body motion

pinash
Posts: 5
Joined: Sun Oct 27, 2013 10:08 pm
Location: tehran

Re: static analysis warning

Post by pinash » Mon Oct 28, 2013 9:30 pm

my node text is:

set Lc [expr 3.2*$m]; # column length
set Lpin1 [expr 0.1*$m]; # column length
set Lb1 [expr 2.*$m]; # lbr1
set Lb2 [expr 3.*$m]; # lbr2
set Lbeam [expr 5.*$m]; # beam length
set Lpin2 [expr 4.8*$m]; # column length
set LGC [expr 5.254*$m]; # beam length GravityColumn

# define NODAL COORDINATES # node#, X Y
node 1 0.0 0.0
node 2 0.0 [expr 1.*$Lc]
node 3 0.0 [expr 2.*$Lc]
node 4 0.0 [expr 3.*$Lc]
node 5 0.0 [expr 4.*$Lc]

node 6 [expr 1.*$Lpin1] [expr 1.*$Lc]
node 7 [expr 1.*$Lpin1] [expr 1.*$Lc]
node 8 [expr 1.*$Lpin1] [expr 2.*$Lc]
node 9 [expr 1.*$Lpin1] [expr 2.*$Lc]
node 10 [expr 1.*$Lpin1] [expr 3.*$Lc]
node 11 [expr 1.*$Lpin1] [expr 3.*$Lc]
node 12 [expr 1.*$Lpin1] [expr 4.*$Lc]
node 13 [expr 1.*$Lpin1] [expr 4.*$Lc]

node 14 [expr 1.*$Lb1] [expr 1.*$Lc]
node 15 [expr 1.*$Lb1] [expr 2.*$Lc]
node 16 [expr 1.*$Lb1] [expr 3.*$Lc]
node 17 [expr 1.*$Lb1] [expr 4.*$Lc]

node 18 [expr 1.*$Lb2] [expr 1.*$Lc]
node 19 [expr 1.*$Lb2] [expr 2.*$Lc]
node 20 [expr 1.*$Lb2] [expr 3.*$Lc]
node 21 [expr 1.*$Lb2] [expr 4.*$Lc]

node 22 [expr 1.*$Lpin2] [expr 1.*$Lc]
node 23 [expr 1.*$Lpin2] [expr 1.*$Lc]
node 24 [expr 1.*$Lpin2] [expr 2.*$Lc]
node 25 [expr 1.*$Lpin2] [expr 2.*$Lc]
node 26 [expr 1.*$Lpin2] [expr 3.*$Lc]
node 27 [expr 1.*$Lpin2] [expr 3.*$Lc]
node 28 [expr 1.*$Lpin2] [expr 4.*$Lc]
node 29 [expr 1.*$Lpin2] [expr 4.*$Lc]

node 30 [expr 1.*$Lbeam] 0.0
node 31 [expr 1.*$Lbeam] [expr 1.*$Lc]
node 32 [expr 1.*$Lbeam] [expr 2.*$Lc]
node 33 [expr 1.*$Lbeam] [expr 3.*$Lc]
node 34 [expr 1.*$Lbeam] [expr 4.*$Lc]

# Representative Gravity Column
node 35 [expr 1.*$LGC] 0.0
node 36 [expr 1.*$LGC] [expr 1.*$Lc]
node 37 [expr 1.*$LGC] [expr 2.*$Lc]
node 38 [expr 1.*$LGC] [expr 3.*$Lc]
node 39 [expr 1.*$LGC] [expr 4.*$Lc]

# BOUNDARY CONDITIONS
fix 1 1 1 1; # Fixed support nodes node DX DY RZ
fix 30 1 1 1; # Fixed support nodes
fix 35 1 1 0; # Fixed support nodes

# Perfectly Pinned Splice
equalDOF 6 7 1 2
equalDOF 22 23 1 2
equalDOF 8 9 1 2
equalDOF 24 25 1 2
equalDOF 10 11 1 2
equalDOF 26 27 1 2
equalDOF 12 13 1 2
equalDOF 28 29 1 2

# Attachment of Gravity Column to Frame
equalDOF 31 36 1 3
equalDOF 32 37 1 3
equalDOF 33 38 1 3
equalDOF 34 39 1 3

# Rigid Diaphragm; Forces the horizontal displacement of column nodes to be equal

equalDOF 2 31 1
equalDOF 3 32 1
equalDOF 4 33 1
equalDOF 5 34 1

can you check my nodes and boundary conditions and find my mistake.please

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