4.14.5.29. KikuchiAikenLRB Material¶
- uniaxialMaterial('KikuchiAikenLRB', matTag, type, ar, hr, gr, ap, tp, alph, beta, <'-T', temp>, <'-coKQ', rk, rq>, <'-coMSS', rs, rf>)
This command is used to construct a uniaxial KikuchiAikenLRB material object. This material model produces nonlinear hysteretic curves of lead-rubber bearings.
matTag
(int)integer tag identifying material
type
(int)rubber type (see note 1)
ar
(float)area of rubber [unit: m^2]
hr
(float)total thickness of rubber [unit: m]
gr
(float)shear modulus of rubber [unit: N/m^2]
ap
(float)area of lead plug [unit: m^2]
tp
(float)yield stress of lead plug [unit: N/m^2]
alph
(float)shear modulus of lead plug [unit: N/m^2]
beta
(float)ratio of initial stiffness to yielding stiffness
temp
(float)temperature [unit: °C]
rk
rq
(float)reduction rate for yielding stiffness (
rk
) and force at zero displacement (rq
)rs
rf
(float)reduction rate for stiffness (
rs
) and force (rf
) (see note 3)
Note
Following rubber types for
type
are available:1
lead-rubber bearing, up to 400% shear strain [Kikuchi et al., 2010 & 2012]
This material uses SI unit in calculation formula. Input arguments must be converted into [m], [m^2], [N/m^2].
rs
andrf
are available if this material is applied to multipleShearSpring (MSS) element. Recommended values arers
= \(\frac{1}{\sum_{i=0}^{n-1}\sin(\pi*i/n)^2}\) andrf
= \(\frac{1}{\sum_{i=0}{n-1}\sin(\pi*i/n)}\), where n is the number of springs in the MSS. For example, when n=8,rs
= 0.2500 andrf
= 0.1989.
See also