recorder elements forces LOCAL COORDINATE

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chen
Posts: 11
Joined: Tue Apr 12, 2005 8:24 am

recorder elements forces LOCAL COORDINATE

Post by chen » Thu May 12, 2005 5:09 am

Hi

I want to recorder the forces at the end of the beams in LOCAL COORDINATE but it doesn't work and I get a rare solution.
I send you the test file and my conclutions.

wipe
model basic -ndm 3 -ndf 6
set L1 10000
set L2 5000
node 1 0 0 0
node 2 0 $L1 0
node 3 $L2 $L1 0
fix 1 1 1 1 1 1 1
fix 3 1 1 1 1 1 1
set R1 9e18
set E 7000.416
set A 10292
set J 767134477
set Iz 383567238
set Iy 383567238
set G 2692.467692
set v 0.3
geomTransf Linear 1 0 0 1
element elasticBeamColumn 1 1 2 $A $E $G $J $Iy $Iz 1
element elasticBeamColumn 2 2 3 $A $E $G $J $Iy $Iz 1
pattern Plain 1 Linear {
eleLoad -ele 1 2 -type -beamUniform 0 100

}
system BandGeneral
constraints Transformation
numberer RCM
algorithm Linear
integrator LoadControl 1
analysis Static
recorder Element -file 1.out -time -ele 1 force
recorder Element -file 1l.out -time -ele 1 localForce
analyze 1
print

When I write:
"recorder Element -file 1.out -time -ele 1 force"

I just get the nodal load corresponding to the linear load already given. Nothing about my forces..



But if I write:
first "recorder Element -file 1.out -time -ele 1 force"
and after "recorder Element -file 1local.out -time -ele 1 localForce"

I get the solution forces in a GLOBAL system in 1.out and the solution forces in a LOCAL system in 1local.out
But the this last one file is wrong. The values of Fz are changed between the node 1 and 2 if I compare these results with the screen results,I mean the print output
Is it normal?
What's it wrong? How can I get the forces in LOCAL COORDINATE
Thanks

silvia
Posts: 3909
Joined: Tue Jan 11, 2005 7:44 am
Location: Degenkolb Engineers
Contact:

Post by silvia » Mon Jun 06, 2005 9:28 am

i am looking at your file, i apologize for the delay, i slipped past.
have you figured this one out?
otherwise, I am able to repeat your error. I will draw the attention to Frank.
however, the force argument in the element recorder is not quite right, you should use globalForce or localForce, even if it still works.

here is what I have:
wipe
model basic -ndm 3 -ndf 6
set L1 10000
set L2 5000
node 1 0 0 0
node 2 0 $L1 0
node 3 $L2 $L1 0
fix 1 1 1 1 1 1 1
fix 3 1 1 1 1 1 1
set R1 9e18
set E 7000.416
set A 10292
set J 767134477
set Iz 383567238
set Iy 383567238
set G 2692.467692
set v 0.3
geomTransf Linear 1 0 0 1
element elasticBeamColumn 1 1 2 $A $E $G $J $Iy $Iz 1
element elasticBeamColumn 2 2 3 $A $E $G $J $Iy $Iz 1
pattern Plain 1 Linear {
eleLoad -ele 1 2 -type -beamUniform 0 100
}
system BandGeneral
constraints Transformation
numberer RCM
algorithm Linear
integrator LoadControl 1
analysis Static
recorder Element -file global_1.out -time -ele 1 globalForce
recorder Element -file local_1.out -time -ele 1 localForce
analyze 1
print
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104

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