BilinearOilDamper MaterialΒΆ

uniaxialMaterial('BilinearOilDamper', matTag, K_el, Cd, Fr=1.0, p=1.0, LGap=0.0, NM=1, RelTol=1e-6, AbsTol=1e-10, MaxHalf=15)

This command is used to construct a BilinearOilDamper material, which simulates the hysteretic response of bilinear oil dampers with relief valve. Two adaptive iterative algorithms have been implemented and validated to solve numerically the constitutive equations within a bilinear oil damper with a high-precision accuracy.

matTag (int) integer tag identifying material
K_el (float) Elastic stiffness of linear spring to model the axial flexibility of a viscous damper (e.g. combined stiffness of the supporting brace and internal damper portion)
Cd (float) Damping coefficient
Fr (float) Damper relief load (default=1.0, Damper property)
p (float) Post-relief viscous damping coefficient ratio (default=1.0, linear oil damper)
LGap (float) Gap length to simulate the gap length due to the pin tolerance
NM (int)

Employed adaptive numerical algorithm (default value NM = 1;

  • 1 = Dormand-Prince54,
  • 2 = 6th order Adams-Bashforth-Moulton,
  • 3 = modified Rosenbrock Triple)
RelTol (float) Tolerance for absolute relative error control of the adaptive iterative algorithm (default value 10^-6)
AbsTol (float) Tolerance for absolute error control of adaptive iterative algorithm (default value 10^-10)
MaxHalf (int) Maximum number of sub-step iterations within an integration step (default value 15)

See also