diff --git a/source/user/manual/material/uniaxialMaterial.rst b/source/user/manual/material/uniaxialMaterial.rst index 6e3e8645..8ebd8c06 100644 --- a/source/user/manual/material/uniaxialMaterial.rst +++ b/source/user/manual/material/uniaxialMaterial.rst @@ -25,6 +25,7 @@ The following subsections contain information about **$matType** uniaxialMaterials/Steel01 uniaxialMaterials/Steel02 + uniaxialMaterials/Steel02M uniaxialMaterials/Steel4 uniaxialMaterials/ASDSteel1D uniaxialMaterials/ReinforcingSteel diff --git a/source/user/manual/material/uniaxialMaterials/Steel02M.rst b/source/user/manual/material/uniaxialMaterials/Steel02M.rst new file mode 100644 index 00000000..e012b6b8 --- /dev/null +++ b/source/user/manual/material/uniaxialMaterials/Steel02M.rst @@ -0,0 +1,87 @@ +.. _steel02m: + +Steel02M Material +^^^^^^^^^^^^^^^^^ + +This command is used to construct the Steel02M uniaxial steel material, a modified Giuffre-Menegotto-Pinto model developed to eliminate overshooting and creeping errors observed in Steel02. It also permits independent definition of key cyclic material parameters in the positive and negative loading directions. + +.. function:: uniaxialMaterial Steel02M $matTag $E $FyPos $FyNeg $alphaPos $alphaNeg $R0 $cR1 $cR2 <$a_pos $a_neg> <$etaPos $etaNeg> <$b_pos $b_neg> +.. csv-table:: + :header: "Argument", "Type", "Description" + :widths: 10, 10, 40 + + $matTag, |integer|, integer tag identifying material + $E, |float|, elastic Young's modulus + $FyPos, |float|, initial yield strength in the positive loading direction :math:`(\sigma_{y0}^{+})` + $FyNeg, |float|, initial yield strength in the negative loading direction :math:`(\sigma_{y0}^{-})`; must be negative + $alphaPos, |float|, strain-hardening ratio in the positive loading direction :math:`(\alpha^{+})` + $alphaNeg, |float|, strain-hardening ratio in the negative loading direction :math:`(\alpha^{-})` + $R0 $cR1 $cR2, 3 |float|, parameters to control the transition from elastic to plastic branches + $a_pos, |float|, cyclic isotropic hardening parameter in the positive loading direction (optional: default = 0.0). + $a_neg, |float|, cyclic isotropic hardening parameter in the negative loading direction (optional: default = 0.0). + $etaPos, |float|, saturation-to-initial-yield-strength ratio in the positive loading direction :math:`(\eta^{+})` (optional: default = 1.5). + $etaNeg, |float|, saturation-to-initial-yield-strength ratio in the negative loading direction :math:`(\eta^{-})` (optional: default = 1.5). + $b_pos, |float|, isotropic hardening rate parameter in the positive loading direction :math:`(b^{+})` (optional: default = 0.8). + $b_neg, |float|, isotropic hardening rate parameter in the negative loading direction :math:`(b^{-})` (optional: default = 0.8). + +.. note:: + + Recommended values: $R0=between 10 and 20, $cR1=0.925, $cR2=0.15 + + +.. _fig-steel02m: + +.. figure:: figures/Steel02M/Steel02M_LivePlot.gif + :align: center + :figclass: align-center + + Comparison of stress-strain response using Steel02 and Steel02M + + +.. figure:: figures/Steel02M/Steel02MParametric.jpeg + :align: center + :figclass: align-center + + llustration of the additional features incorporated in the Steel02M material model, showing independent definitions in the positive and negative directions of: (a) strain hardening ratios, (b) initial yield strengths, (c) isotropic hardening rates, and (d) saturation-to-initial yield strength ratios + + + +.. admonition:: Example + + Download the Steel02M examples: :download:`Steel02M_Example.rar `. The archive contains the input files; recorder output files are generated when the model is executed. + + The following example defines a ``Steel02M`` material using all material parameters. For additional examples and implementation details, see `Steel02M GitHub repository `_. + + .. code-block:: tcl + + set matTag 1 + set E 200000.0 + set FyPos 300.0 + set FyNeg -300 + set alphaPos 0.0196 + set alphaNeg 0.0196 + set R0 20.0 + set cR1 0.916 + set cR2 0.15 + set a_pos 0.05 + set a_neg 0.074 + set etaPos 1.50 + set etaNeg 1.50 + set b_pos 0.80 + set b_neg 0.80 + + uniaxialMaterial Steel02M $matTag $E $FyPos $FyNeg $alphaPos $alphaNeg $R0 $cR1 $cR2 $a_pos $a_neg $etaPos $etaNeg $b_pos $b_neg + +References +========== + +Kolay, C., Karmakar, S., Kumar, B., and Kakoty, H. (2026). *An Improved Giuffré–Menegotto–Pinto Model: Implementation in OpenSees and Verification With Experimental Results.* Earthquake Engineering & Structural Dynamics. DOI: https://doi.org/10.1002/eqe.70266 + + +Code inquiry or bug reporting +========== + +- Chinmoy Kolay, Indian Institute of Technology kanpur, e-mail: ckolay@iitk.ac.in +- Sukanya Karmakar, Indian Institute of Technology kanpur, e-mail: sukanyak@iitk.ac.in +- Baban Kumar, Indian Institute of Technology kanpur, e-mail: babank@iitk.ac.in +- Hironmoy kakoty, Indian Institute of Technology kanpur, e-mail: kakoty@iitk.ac.in diff --git a/source/user/manual/material/uniaxialMaterials/Steel02M_Example.rar b/source/user/manual/material/uniaxialMaterials/Steel02M_Example.rar new file mode 100644 index 00000000..3bb4e046 Binary files /dev/null and b/source/user/manual/material/uniaxialMaterials/Steel02M_Example.rar differ diff --git a/source/user/manual/material/uniaxialMaterials/figures/Steel02M/Steel02MParametric.jpeg b/source/user/manual/material/uniaxialMaterials/figures/Steel02M/Steel02MParametric.jpeg new file mode 100644 index 00000000..a5871210 Binary files /dev/null and b/source/user/manual/material/uniaxialMaterials/figures/Steel02M/Steel02MParametric.jpeg differ diff --git a/source/user/manual/material/uniaxialMaterials/figures/Steel02M/Steel02M_LivePlot.gif b/source/user/manual/material/uniaxialMaterials/figures/Steel02M/Steel02M_LivePlot.gif new file mode 100644 index 00000000..47339fd7 Binary files /dev/null and b/source/user/manual/material/uniaxialMaterials/figures/Steel02M/Steel02M_LivePlot.gif differ