BInel2dFrm_wEPLHM

Purpose

2d elasto-plastic, linear hardening basic frame element with hinge offsets

Synopsis

BElemResp = BInel2dFrm_wEPLHM (action,L,BElemData,BElemState)

Description

BINELP2dFRM_WEPLHM 2d elasto-plastic, linear hardening basic frame element with hinge offsets
  BELEMRESP = BINELP2dFRM_WEPLHM (ACTION,L,BELEMDATA,BELEMSTATE)
  the function determines the 2d response of an elasto-plastic basic frame element of length L 
  with linear elastic axial response and elasto-plasic flexural response
  with linear isotropic and kinematic hardening at two plastic hinges
  that may be offset from the element ends (series model)
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  When the character variable ACTION has one of the following values,
  the function performs the listed operations and returns the results in BELEMRESP:
  ACTION = 'chec': check element property data for omissions and assign default values
           'init': initialize element history variables
           'forc': report basic element forces
           'stif': report basic element stiffness matrix and basic element forces
           'post': report post-processing information
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  The data structure BELEMRESP stands for the following data object(s) for each ACTION:
  BELEMRESP = BELEMDATA    for action = 'chec'
  BELEMRESP = BELEMSTATE   for action = 'init'
  BELEMRESP = BELEMSTATE   for action = 'stif'
  BELEMRESP = BELEMSTATE   for action = 'forc'
  BELEMRESP = BELEMPOST    for action = 'post'
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  BELEMDATA is a data structure with basic element property information; it has the fields
         E   = Young's Modulus
         A   = cross-sectional area
         I   = moment of inertia
         Mp  = plastic moment capacity at plastic hinges near ends i, j ( Mp = [Mpi , Mpj] )
         Hir = isotropic hardening modulus ratio
         Hkr = kinematic hardening modulus ratio
         HngOff = offset location of plastic hinges as %L (default [0 0])
         w      = uniformly distributed element load [wx;wy];
         YFtol  = yield criterion tolerance (default = 1e-12)
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  BELEMSTATE is a data structure with the current basic element state; it has the fields
         v     = vector of total element deformations
         k     = basic element stiffness matrix; updated under ACTION = 'stif'
         q     = basic element forces; updated under ACTION = 'stif' or 'forc'
         Past  = element history variables at last converged state
         Pres  = current element history variables
         the element history variables of this element are
             ehp   = plastic hinge   deformations   (2x1 array)
             Mbk   = back forces at flexural hinges (2x1 array)
             alpha = isotropic hardening variable   (2x1 array)

Cross-Reference Information

This function calls:

• ElementLoading determines current distributed element load value