uniaxialMaterial

[ehsanala]

hi
I have become familiar with the behavior of uniaxialMaterial SMA to built a simple model . Why stress-strain curve is not drawn?
Can I use the uniaxialMaterial SelfCentering instead of uniaxialMaterial SMA?

Do these two materials have similar?
Do these two materials applications are the same?

Please give more explanation
regard

wipe

file mkdir b3

model basic -ndm 2 -ndf 3

node 1 0. 0.
node 3 0. 3.

fix 1 1 1 1


mass 3 200. 1.e-9 1.e-9


#geomTransf Linear 1
geomTransf PDelta 1



#uniaxialMaterial SMA $matTag $E $eps_L $sig_AM_s $sig_AM_f $sig_MA_s $sig_MA_f

uniaxialMaterial SMA 1 27579.e6 0.035 414.e6 550.e6 390.e6 200.e6


#
#set k1 27579.e6; # Initial Stiffness
#set k2 3400.e6; # Post-Activation Stiffness (0<$k2<$k1)
#set sigAct 414.e6; # Forward Activation Stress/Force
#set beta 0.39; # Ratio of Forward to Reverse Activation Stress/Force
#set epsSlip 0.055; # slip Strain/Deformation (if $epsSlip = 0, there will be no slippage)
#set epsBear 0.055; # Bearing Strain/Deformation (if $epsBear = 0, there will be no bearing)
#set rBear 1.; # Ratio of Bearing Stiffness to Initial Stiffness $k1
#uniaxialMaterial SelfCentering 1 $k1 $k2 $sigAct $beta $epsSlip $epsBear $rBear;





#
section Fiber 1 {
patch quad 1 2 3 0.0348 0.023 0.0348 -0.023 0.04 -0.023 0.04 0.023
patch quad 1 2 8 -0.0348 0.0019 -0.0348 -0.0019 0.0348 -0.0019 0.0348 0.0019
patch quad 1 2 3 -0.04 0.023 -0.04 -0.023 -0.0348 -0.023 -0.0348 0.023
}



element nonlinearBeamColumn 1 1 3 10 1 1


recorder Node -file b3/disno3.txt -time -node 3 -dof 1 2 3 disp
recorder Element -file b3/ssele1.txt -time -ele 1 section 1 fiber 0.1 0.1 stressStrain



pattern Plain 1 Linear {
load 3 1. 0. 0.
}



#puts [eigen 2]
#puts "t1=[expr (3.1415*2)/pow([lindex [eigen 2] 0 0],0.5)]"
#puts "t2=[expr (3.1415*2)/pow([lindex [eigen 2] 1 0],0.5)]"
#


recorder plot b3/ssele1.txt S-S 50 50 500 500 -columns 3 2
#
#recorder display figure 570 50 500 500 -wipe
#vup 0 1 0
#vpn 0 0 1
#prp 1 1 1
#display 1 5 1


constraints Plain
numberer Plain
system BandGeneral
test EnergyIncr 1.e-7 60
algorithm Newton

set disploop [list 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0]
for {set i 1} {$i<=[llength $disploop]} {incr i 1} {
set dispincr [expr 1.0*pow((-1.0),[expr $i-1])*[lindex $disploop [expr $i-1]]/100]
integrator DisplacementControl 3 1 [expr 2*$dispincr];
analysis Static
analyze 500
}

[brag006]

OpenSees is not a drawing tool. Use a recorder to capture the output you want and plot using some other software (excel, matlab etc.)
Each material is usually developed for the specific purpose so use the material that meets your requirements. You need to understand the theory for this. Read the references and get a better understanding of the models you are using.

[ehsanala]

thanks

I asked because I had doubts.
Can I use the uniaxialMaterial SelfCentering instead of uniaxialMaterial SMA?

[mhscott]

You should try each model and see which is most appropriate for what you are attempting to simulate.

[fmk]

the SMA or Shape Memory Alloy material was removed a long time ago!

[srishtibanerji]

Hi Frank...
Please give me some suggestion on modelling shape memory alloy material in opensees.
Its very important for my project.

Thank you so much
Srishti

[esi_opensees]

You can run OpenSees 2.0.0 version

[srishtibanerji]

Thanks for your reply.
Will uniaxial material SMA work in this version?

[srishtibanerji]

Also, from where can i download Opensees 2.0.0 version.
I am unable to find in on the website.
Thanks!

[fmk]

this will be avail temporarily:
http://opensees.berkeley.edu/OpenSees/c ... .0.exe.zip