# Semi-analytical models for Stiffeners (`compmech.stiffener`)

This module has all stiffener’s formulations used along other classes.

class `compmech.stiffener.``BladeStiff1D`(bay, mu, panel1, panel2, ys, bb, bf, bstack, bplyts, blaminaprops, fstack, fplyts, flaminaprops)

  Blade Stiffener using 1D Formulation for Flange

  Blade-type of stiffener model using a 1D formulation for the flange and a 2D formulation for the padup (base):

                 || --> flange       |
                 ||                  |-> stiffener
               ======  --> padup     |
      =========================  --> panels
         Panel1      Panel2

  Both the flange and the padup are optional, but one must exist.

  Each stiffener has a constant coordinate.

  Methods

  `calc_k0`([size, row0, col0, silent, finalize]) | Calculate the linear constitutive stiffness matrix
  `calc_kG0`([size, row0, col0, silent, finalize, c]) | Calculate the linear geometric stiffness matrix
  `calc_kM`([size, row0, col0, silent, finalize]) | Calculate the mass matrix

  `calc_k0`(size=None, row0=0, col0=0, silent=False, finalize=True)

    Calculate the linear constitutive stiffness matrix

  `calc_kG0`(size=None, row0=0, col0=0, silent=False, finalize=True, c=None)

    Calculate the linear geometric stiffness matrix

  `calc_kM`(size=None, row0=0, col0=0, silent=False, finalize=True)

    Calculate the mass matrix

class `compmech.stiffener.``BladeStiff2D`(bay, mu, panel1, panel2, ys, bb, bf, bstack, bplyts, blaminaprops, fstack, fplyts, flaminaprops)

  Blade Stiffener using 2D Formulation for Flange

  Blade-type of stiffener model using a 2D formulation for the flange and a 2D formulation for the base (padup):

                 || --> flange       |
                 ||                  |-> stiffener
               ======  --> padup     |
      =========================  --> panels
         Panel1      Panel2

  Both the flange and the base are optional. The stiffener’s base is modeled using the same approximation functions as the skin, with the proper offset.

  Each stiffener has a constant coordinate.

  Methods

  `calc_k0`([size, row0, col0, silent, finalize]) | Calculate the linear constitutive stiffness matrix
  `calc_kG0`([size, row0, col0, silent, finalize, c]) | Calculate the linear geometric stiffness matrix
  `calc_kM`([size, row0, col0, silent, finalize]) | Calculate the mass matrix

  `calc_k0`(size=None, row0=0, col0=0, silent=False, finalize=True)

    Calculate the linear constitutive stiffness matrix

  `calc_kG0`(size=None, row0=0, col0=0, silent=False, finalize=True, c=None)

    Calculate the linear geometric stiffness matrix

  `calc_kM`(size=None, row0=0, col0=0, silent=False, finalize=True)

    Calculate the mass matrix

class `compmech.stiffener.``TStiff2D`(bay, mu, panel1, panel2, ys, bb, bf, bstack, bplyts, blaminaprops, fstack, fplyts, flaminaprops, model='tstiff2d_clt_donnell_bardell')

  T Stiffener using 2D Formulation for the Base and Flange

  T-type of stiffener model using a 2D formulation for the flange and a 2D formulation for the base:

                 || --> flange       |
                 ||                  |-> stiffener
               ======  --> base      |
      =========================  --> panels
         Panel1      Panel2

  The difference between this model and :class:’.BladeStiff2D’ is that here the stiffener’s base has independent field variables allowing the simulation of skin-stiffener debounding effects.

  Each stiffener has a constant coordinate.

  Methods

  `calc_k0`([size, row0, col0, silent, finalize]) | Calculate the linear constitutive stiffness matrix
  `calc_kG0`([size, row0, col0, silent, finalize, c]) | Calculate the linear geometric stiffness matrix
  `calc_kM`([size, row0, col0, silent, finalize]) | Calculate the mass matrix

  `calc_k0`(size=None, row0=0, col0=0, silent=False, finalize=True)

    Calculate the linear constitutive stiffness matrix

  `calc_kG0`(size=None, row0=0, col0=0, silent=False, finalize=True, c=None)

    Calculate the linear geometric stiffness matrix

  `calc_kM`(size=None, row0=0, col0=0, silent=False, finalize=True)

    Calculate the mass matrix