Bilin Material

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Revision as of 15:23, 6 September 2010 by D.lignos (talk | contribs)
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This command is used to construct a bilin something or other

uniaxialMaterial Bilin $matTag $K0 $as_Plus $as_Neg $My_Plus $My_Neg $Lamda_S $Lamda_C $Lamda_A $Lamda_K $c_S $c_C $c_A $c_K $theta_p_Plus $theta_p_Neg $theta_pc_Plus $theta_pc_Neg $Res_Pos $Res_Neg $theta_u_Plus $theta_u_Neg $D_Plus $D_Neg

$matTag integer tag identifying material
$K0 elastic stiffness
$as_Plus strain hardening ratio for positive loading direction
$as_Neg strain hardening ratio for negative loading direction
$My_Plus effective yield strength for positive loading direction
$My_Neg effective yield strength for negative loading direction
$Lamda_S Cyclic deterioration parameter for strength deterioration
$Lamda_C Cyclic deterioration parameter for post-capping strength deterioration
$Lamda_A Cyclic deterioration parameter for acceleration reloading stiffness deterioration (is not a deterioration mode for a component with Bilinear hysteretic response).
$Lamda_K Cyclic deterioration parameter for unloading stiffness deterioration
$c_S rate of strength deterioration
$c_C rate of post-capping strength deterioration
$c_A rate of accelerated reloading deterioration
$c_K rate of unloading stiffness deterioration
$theta_p_Plus pre-capping rotation for positive loading direction (often noted as plastic rotation capacity)
$theta_p_Neg pre-capping rotation for negative loading direction (often noted as plastic rotation capacity)
$theta_pc_Plus post-capping rotation for positive loading direction
$theta_pc_Neg post-capping rotation for negative loading direction
$Res_Pos residual strength ratio for positive loading direction
$Res_Neg residual strength ratio for negative loading direction
$theta_u_Plus ultimate rotation capacity for positive loading direction
$theta_u_Neg ultimate rotation capacity for negative loading direction
$D_Plus rate of cyclic deterioration in the positive loading direction (this parameter is used to create assymetric hysteretic behavior for the case of a composite beam)
$D_Neg rate of cyclic deterioration in the negative loading direction (this parameter is used to create assymetric hysteretic behavior for the case of a composite beam)


Image from: Lignos, D. G., Krawinkler, H. and Whittaker, A.S. (2010). "Prediction and validation of sidesway collapse of two scale models of a 4-story steel moment frame", Earthquake Engineering and Structural Dynamics, EESD, (Accepted for publication, June 14th 2010).

Lignos, D.G., Krawinkler, H. (2009). “Sidesway collapse of deteriorating structural systems under seismic excitations,” Report No.TB 172, The John A. Blume Earthquake Engineering Research Center, Department of Civil Engineering, Stanford University, Stanford, CA.


Other relevant references:


Code Developed by : by Dr. Dimitrios G. Lignos, McGill University and was implemented by Dr. Theodore Karavasilis, Oxford University