4.15.14. Isolator2spring SectionΒΆ

section('Isolator2spring', matTag, tol, k1, Fyo, k2o, kvo, hb, PE, Po=0.0)

This command is used to construct an Isolator2spring section object, which represents the buckling behavior of an elastomeric bearing for two-dimensional analysis in the lateral and vertical plane. An Isolator2spring section represents the resultant force-deformation behavior of the bearing, and should be used with a zeroLengthSection element. The bearing should be constrained against rotation.

secTag (int) unique section tag
tol (float) tolerance for convergence of the element state. Suggested value: E-12 to E-10. OpenSees will warn if convergence is not achieved, however this usually does not prevent global convergence.
k1 (float) initial stiffness for lateral force-deformation
Fyo (float) nominal yield strength for lateral force-deformation
k2o (float) nominal postyield stiffness for lateral force-deformation
kvo (float) nominal stiffness in the vertical direction
hb (float) total height of elastomeric bearing
PE (float) Euler Buckling load for the bearing
Po (float) axial load at which nominal yield strength is achieved (optional)