how to calculate structure's energy

[leiloo]

yes, i can.
But the stiffness matrix of structure with damper, that obtained from printA command,is correct?


Your tips are very helpful

[leiloo]

in structure with viscoelastic damper, can I calculate the stiffness matrix with "printA" command?
the calculated answer with this method is correct?

integrator LoadControl 1
system FullGeneral
analysis Static
analyze 1
printA -file Stiff.out


wipeAnalysis
rayleigh 0.0 0.0 0.0 0.0
system FullGeneral
integrator NewmarkExplicit 0.5
analysis Transient
analyze 1 1.
printA -file mass.out


thanks

[selimgunay]

To get the stiffness matrix, 1) you can use

integrator Newmark 0.5 0.25

and set all the mass and damping to zero

2) or you don't need to modify mass and damping and use the displacementcontrol integrator.

[leiloo]

Are the commands coming below, correct?
do I have to write commands related to gravity loads and gravity commands before these?

integrator DisplacementControl 42 1 0.002
system FullGeneral
analysis Static
analyze 1500
printA -file Stiff.out

wipeAnalysis

system FullGeneral
integrator NewmarkExplicit 0.5
algorithm NewtonLineSearch
analysis Transient
analyze 1 1.
printA -file mass.out

thanks

[selimgunay]

Reinforced concrete stiffness gets affected by gravity loading, so for RC you need to use gravity loading before these commands otherwise you don't need it.

[leiloo]

is the following viscoelastice damper model correct?
is making the materials parallel correct?

uniaxialMaterial Elastic 1 16.77e6
uniaxialMaterial Viscous 2 2498e3 0.5
uniaxialMaterial Parallel 3 1 2

element twoNodeLink 67 8 16 -mat 3 -dir 1

thanks

[Gholamreza]

Informative