OpenSees Navigator

[narges047]

Hi,

Can I conduct “Static Reversed Cyclic Analysis” (Cyclic Pushover Analysis) using OpenSees Navigator?

If yes, where and how I should introduce the maximum displacements at each cycle to the OpenSees Navigator?

Thanks for your time,

[silvia]

you can do it with BuildingTcl

[narges047]

Dear Silvia,

Thank you very much for your time and invaluable help.
I am working on this for 2-3 days . For one-directional pushover I know how to build the Tcl but I have one main problem dealing with Cyclic Pushover Analysis!!

Here is my problem:
How I can reverse the direction of load in any cycle?


If I use displacement control, I have to introduce only one value of dU in Navigator
If I use force control, there is only one value (positive or negative ) for load increments.

Thank you very much for your help and time,

[silvia]

i don't use Navigator.
you should look at BuildingTcl, the gui i developed, it has the cyclic-loading option.

look at the announcement message at the top of this board.

[fmk]

in tcl, both cyclic force and displacement control are very simple .. here is a link to force control:

[url]
http://opensees.berkeley.edu/community/ ... hp?t=20634
[/url]

and here is the example modified for displacement control:

[code]
model basic -ndm 2 -ndf 2

# model
set periodStruct 1.0;
set L 1.0
set A 1.0;
set m 1.0;

#derived quantaties
set PI 3.14159

set fStruct [expr 1.0/$periodStruct]
set wStruct [expr 2.0 * $PI / $periodStruct]
set K [expr $wStruct * $wStruct * $m]
set E [expr $L * $K / $A]

wipe
model basic -ndm 1 -ndf 1

node 1 0.0
node 2 $L -mass $m
uniaxialMaterial Elastic 1 $E
element truss 1 1 2 $A 1

fix 1 1

timeSeries Linear 1

pattern Plain 1 1 {
load 2 1.0
}

integrator LoadControl 1.0
constraints Plain
system BandGen
algorithm Linear
numberer Plain
constraints Plain
analysis Static

recorder Node -file rxn.out -time -node 1 -dof 1 reaction

foreach {dU numIncr} {0.1 10 -0.1 10 -0.1 10 0.1 10 0.1 20 -0.1 20 -0.1 20 0.1 20} {
integrator DisplacementControl 2 1 $dU
analyze $numIncr
set disp [nodeDisp 2 1]
puts "$disp"
}

[/code]

[narges047]

Thank you very much Silvia, "BuildingTcl" is a piece of great work. Thanks for your time.



I have a question and I would appreciate if u make it clear for me:

How I can define pin-pin connections for a nonlinear beam-column element
(at both ends).


Please not that:
1) I have to use nonlinear beam-column element for my buckling model (so truss element is not working for me)
2) I can not use zero length element with low rotational values since I dont want messing up the stiffness matrix. (I want to analyze a big model with over 300 elements)

Thanks again for your time

[silvia]

i'd have to implement that....
it's a nice idea.

[narges047]

Silvia,

Thank you very much for your time and clarification.