J:/Tecgraf/prj/femoop/trunk/elc/elctruss.h

// -------------------------------------------------------------------------
// ElcTruss.h - This header file contains methods for truss elements.
// -------------------------------------------------------------------------
// Protected methods:
// -------------------------------------------------------------------------
//
// void DisplToArray( sNodeDispl *displ, double *u )
//
//      displ      -  nodal displacements (u,v,w)                (  in )
//      u          -  nodal displacements (array)                ( out )
//
// Transforms displacements from structure (u,v,w) form to array form.
// Obs: displ[0]..displ[1] => u[0]..u[5]
// -------------------------------------------------------------------------
//
// void B0Matrix( sNodeCoord *coord, double *B0 )
//
//      coord      -  nodal coordinates (x,y,z)                  (  in )
//      B0         -  linear strain-displacement matrix          ( out )
//
// Evaluates the linear strain-displacement matrix.
// -------------------------------------------------------------------------
//
// void BlMatrix( sNodeDispl *displ, double *Bl )
//
//      displ      -  nodal displacements (u,v,w)                (  in )
//      B0         -  nonlinear strain-displacement matrix       ( out )
//
// Evaluates the nonlinear strain-displacement matrix for the given
// displacements.
// -------------------------------------------------------------------------
//
// $Author: evandro $
// $Revision: 1.5 $
// $Date: 2000/04/05 13:31:42 $
// $State: Exp $
//
// -------------------------------------------------------------------------

#ifndef _ELCTRUSS_H
#define _ELCTRUSS_H

#include "gbldefs.h"
#include "elcbar.h"

// -------------------------------------------------------------------------
// Definition of the Space Truss Element Class:
//
class cElcTruss : public cElcBar
{
 protected:
          double  _dEA;          // Section stiffness (E * A)
          double  _dForce;       // Axial force

 public:
                  cElcTruss      ( void );
  virtual        ~cElcTruss      ( void );
          int     ThermalEffects ( void ) { return 1; }
          double  GetVol         ( void );
          void    Stiffness      ( double * );
          void    GeoStiffness   ( double * );
          int     InternalForce  ( double * );
          void    CalcIntPtStress( void );
          void    NodeStress     ( sTensor * );
          double  DsaVolumeAm    ( sNodeCoord * );
          void    DsaIntForceAm  ( sNodeCoord *, double * );
//          void    DsaStiffMatAm  ( sNodeCoord *, double *, double * );
//          void    DsaGeoStiffAm  ( sNodeCoord *, double *, double *,
//                                   double * );
          void    DsaStressAm    ( int, sNodeCoord *, double *, double ** );


 protected:
          void    CompRotMat     ( void );
          double  GetLength      ( sNodeCoord * );
          void    DisplToArray   ( sNodeDispl *, double * );
          void    ElmVector      ( sNodeCoord *, double * );
          void    B0Matrix       ( sNodeCoord *, double *, double * );
          void    DsaDerB0Matrix ( sNodeCoord *, sNodeCoord *, double *,
                                   double * );
};

// -------------------------------------------------------------------------
// Definition of the Space Truss/Total Lagrangian Element Class:
//
class cElcTrussTL : public cElcTruss
{
 public:
                  cElcTrussTL    ( void );
                 ~cElcTrussTL    ( void ) { }
          int     GeoNonLinear   ( void ) { return 1; }
          void    Stiffness      ( double * );
          int     InternalForce  ( double * );
          void    CalcIntPtStress( void );
          void    DsaIntForceAm  ( sNodeCoord *, double * );
          void    DsaStiffMatAm  ( sNodeCoord *, double *, double * );
          void    DsaStressAm    ( int, sNodeCoord *, double *, double ** );

 protected:
          void    UpdCoord       ( sNodeCoord *, sNodeDispl * );
          void    BlMatrix       ( sNodeCoord *, sNodeDispl *, double *,
                                   double * );
          void    DsaDerBlMatrix ( sNodeCoord *, sNodeDispl *, sNodeCoord *,
                                   double * );
};

// -------------------------------------------------------------------------
// Definition of the Space Truss/Corotational Element Class:
//
class cElcTrussCR : public cElcTrussTL
{
 public:
                  cElcTrussCR    ( void );
                 ~cElcTrussCR    ( void ) { }
          void    Stiffness      ( double * );
          int     InternalForce  ( double * );
          void    CalcIntPtStress( void );

 protected:
          void    RVector        ( sNodeCoord *, double *, double * );
};

#endif

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