BoucWen Material: Difference between revisions

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REFERENCES:
REFERENCES:


Haukaas, T. and Der Kiureghian, A. (2003). "Finite element reliability and sensitivity methods for performance-based earthquake engineering." REER report, PEER-2003/14.
Haukaas, T. and Der Kiureghian, A. (2003). "Finite element reliability and sensitivity methods for performance-based earthquake engineering." REER report, PEER-2003/14 [http://peer.berkeley.edu/publications/peer_reports/reports_2003/0314.pdf].


Baber, T. T. and Noori, M. N. (1985). "Random vibration of degrading, pinching systems." Journal
Baber, T. T. and Noori, M. N. (1985). "Random vibration of degrading, pinching systems." Journal

Revision as of 21:18, 18 November 2010




This command is used to construct a uniaxial Bouc-Wen smooth hysteretic material object. This material model is an extension of the original Bouc-Wen model that includes stiffness and strength degradation (Baber and Noori (1985)).

uniaxialMaterial BoucWen $matTag $alpha $ko $n $gamma $beta $Ao $deltaA $deltaNu $deltaEta

$matTag integer tag identifying material
$alpha ratio of post-yield stiffness to the initial elastic stiffenss (0< <math>\alpha</math> <1)
$ko initial elastic stiffness
$n parameter that controls transition from linear to nonlinear range (as n increases the transition becomes sharper; n is usually grater or equal to 1)
$gamma $beta parameters that control shape of hysteresis loop; depending on the values of <math>\gamma</math> and <math>\beta</math> softening, hardening or quasi-linearity can be simulated (look at the NOTES)
$Ao $deltaA parameters that control tangent stiffness
$deltaNu $deltaEta parameters that control material degradation (parameter $deltaEta also controls yielding strain)


NOTES:

  1. Parameters <math>\gamma</math> and <math>\beta</math> are usually in the range from 0 to 1. Depending on the values of <math>\gamma</math> and <math>\beta</math> softening, hardening or quasi-linearity can be simulated. The hysteresis loop will exhibit softening for the following cases: (a) <math>\beta</math> + <math>\gamma</math> > 0 and <math>\beta</math> - <math>\gamma</math> > 0, (b) <math>\beta</math>+<math>\gamma</math> >0 and <math>\beta</math>-<math>\gamma</math> <0, and (c) <math>\beta</math>+<math>\gamma</math> >0 and <math>\beta</math>-<math>\gamma</math> = 0. The hysteresis loop will exhibit hardening if <math>\beta</math>+<math>\gamma</math> < 0 and <math>\beta</math>-<math>\gamma</math> > 0, and quasi-linearity if <math>\beta</math>+<math>\gamma</math> = 0 and <math>\beta</math>-<math>\gamma</math> > 0.


REFERENCES:

Haukaas, T. and Der Kiureghian, A. (2003). "Finite element reliability and sensitivity methods for performance-based earthquake engineering." REER report, PEER-2003/14 [1].

Baber, T. T. and Noori, M. N. (1985). "Random vibration of degrading, pinching systems." Journal of Engineering Mechanics, 111(8), 1010-1026.

Bouc, R. (1971). "Mathematical model for hysteresis." Report to the Centre de Recherches Physiques, pp16-25, Marseille, France.

Wen, Y.-K. (1976). \Method for random vibration of hysteretic systems." Journal of Engineering Mechanics Division, 102(EM2), 249-263.