Hysteretic material

[nikhilnbr]

i am new to this software opensees. i want to do a time history analysis for a 2D 4 story RC frame. for that i need to define a hysteretic material
how to find out the properties to be used as input for the hysteretic material,
How to find out the values for these parameters

$s1p $e1p stress and strain (or force & deformation) at first point of the envelope in the positive direction
$s2p $e2p stress and strain (or force & deformation) at second point of the envelope in the positive direction
$s3p $e3p stress and strain (or force & deformation) at third point of the envelope in the positive direction (optional)
$s1n $e1n stress and strain (or force & deformation) at first point of the envelope in the negative direction
$s2n $e2n stress and strain (or force & deformation) at second point of the envelope in the negative direction
$s3n $e3n stress and strain (or force & deformation) at third point of the envelope in the negative direction (optional)
$pinchx pinching factor for strain (or deformation) during reloading
$pinchy pinching factor for stress (or force) during reloading
$damage1 damage due to ductility: D1(mu-1)
$damage2 damage due to energy: D2(Eii/Eult)
$beta power used to determine the degraded unloading stiffness based on ductility, mu-beta (optional, default=0.0)

[fmk]

you need to play with some simple stress-strain analysis until you understand the material and get it doing what you want.

http://opensees.berkeley.edu/OpenSees/m ... l/4052.htm

[nikhilnbr]

can u suggest the range of values that these properties can have?

My purpose is to do Time history analysis for a 2D RC Frame .What model i should use for getting appropriate results

[gor]

I just posted something here that uses hysteretic material to test out a material. Play around with this and you will see what affects what. Youll need to define an analysis because mine uses another subroutine, but this is the basic model.

http://opensees.berkeley.edu/community/ ... =2&t=62229