Reinforcing Steel Material

Contact Authors:	Jon Mohle M.S., P.E.
	Sashi Kunnath: http://cee.engr.ucdavis.edu/faculty/kunnath/kunnath.htm

This command is used to construct a ReinforcingSteel uniaxial material object. This object is intended to be used in a reinforced concrete fiber section as the steel reinforcing material.

uniaxialMaterial ReinforcingSteel $matTag $fy $fu $Es $Esh $esh $eult < -GABuck $lsr $beta $r $gama > < -DMBuck $lsr < $alpha >> < -CMFatigue $Cf $alpha $Cd > < -IsoHard <$a1 <$limit> > >

---

$matTag	integer tag identifying material
$matTag	unique material object integer tag
$fy	Yield stress in tension (see Figure 1)
$fu	Ultimate stress in tension
$Es	Initial elastic tangent
$Esh	Tangent at initial strain hardening
$esh	Strain corresponding to initial strain hardening
$eult	Strain at peak stress
-GABuck	Buckling Model Based on Gomes and Appleton (1997)

{|

| style="width:150px;" | $lsr || Slenderness Ratio (see Figure 2) |- | $beta || Amplification factor for the buckled stress strain curve. (see Figure 3) |-valign=top | $r ||Buckling reduction factor

r can be a real number between [0.0 and 1.0]

r=1.0 full reduction (no buckling)

r=0.0 no reduction

0.0<r<1.0 linear interpolation between buckled and unbuckled curves

|- | $gamma || Buckling constant (see Figures 3 and 4) |}

-DMBuck

Buckling model based on Dhakal and Maekawa (2002)

{|

| style="width:150px;" | $lsr || Slenderness Ratio (see Figure 2) |-valign=top

| $alpha || Adjustment Constant usually between 0.75 and 1.0

Default: alpha=1.0, this parameter is optional.

|}

-CMFatigue

Coffin-Manson Fatigue and Strength Reduction

{|

| style="width:150px;" | $Cf || Coffin-Manson constant C (see Figure 5) |- | $alpha || Coffin-Manson constant a (see Figure 5) |- | $Cd || Cyclic strength reduction constant (see Figure 6 and Equation 3) |}

-IsoHard

Isotropic Hardening / Diminishing Yield Plateau

{|

| style="width:150px;" | $a1 || Hardening constant (default = 4.3) |- | $limit || Limit for the reduction of the yield plateau. % of original plateau length to remain (0.01 < limit < 1.0 )

Limit =1.0, then no reduction takes place (default =0.01)

|}

-MPCurveParams

Menegotto and Pinto Curve Parameters  see Fig 6b

$R1

(default = 0.333)

$R2

(default = 18)

$R3

(default = 4)

-MPCurveParams

Menegotto and Pinto Curve Parameters see Fig 6b

{|

| style="width:150px;" | $R1 || (default = 0.333) |- | $R2 || (default = 18) |- | $R3 || (default = 4) |}