KikuchiAikenHDR Material

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This command is used to construct a uniaxial KikuchiAikenHDR material object. This material model produces nonlinear hysteretic curves of high damping rubber bearings (HDRs).

uniaxialMaterial KikuchiAikenHDR $matTag $tp $ar $hr <-coGHU $cg $ch $cu> <-coMSS $rs $rf>

$matTag integer tag identifying material
$tp rubber type (see note 1)
$ar area of rubber [unit: m^2] (see note 2)
$hr total thickness of rubber [unit: m] (see note 2)
$cg $ch $cu correction coefficients for equivalent shear modulus ($cg), equivalent viscous daming ratio ($ch), ratio of shear force at zero displacement ($cu).
$rs $rf reduction rate for stiffness ($rs) and force ($rf) (see note 3)

NOTES:

1) Following rubber types for $tp are available:

X0.6 Bridgestone X0.6, standard compressive stress, up to 400% shear strain
X0.6-0MPa Bridgestone X0.6, zero compressive stress, up to 400% shear strain
X0.4 Bridgestone X0.4, standard compressive stress, up to 400% shear strain
X0.4-0MPa Bridgestone X0.4, zero compressive stress, up to 400% shear strain
X0.3 Bridgestone X0.3, standard compressive stress, up to 400% shear strain
X0.3-0MPa Bridgestone X0.3, zero compressive stress, up to 400% shear strain

2) This material uses SI unit in calculation formula. $ar and $hr must be converted into [m^2] and [m], respectively.

3) $rs and $rf are available if this material is applied to multipleShearSpring (MSS) element. Recommended values are $rs=1/sum(i=0,n-1){ sin(pi*i/n)^2} and $rf=1/sum(i=0,n-1){sin(pi*i/n)}, where n is the number of springs in the MSS. For example, when n=8, $rs=0.2500, $rf=0.1989.


EXAMPLE:

KikuchiAikenHDR_sample.tcl


Code Developed by: mkiku