J:/Tecgraf/prj/femoop/trunk/shp/shpquad5.h

// -------------------------------------------------------------------------
// shpquad5.h    - this file contains  methods  for the 5-noded
//                 quadrilateral  element shape.
// -------------------------------------------------------------------------
// Remarks:
// -------------------------------------------------------------------------
// This shape contains an extra node at center for displacement
// interpolation.
// The bubble function  [(1-r*r)*(1-s*s)]  is  associated to this node in
// order to compute the element stiffness matrix.
// After that,  the stiffness matrix is condensed to obtain the final
// element stiffness matrix  in terms of the original corner nodes
// (as in a Q4 element).
// -------------------------------------------------------------------------
// The numbering scheme is:
//
//                    s
//                    ^
//                    |    (natural coord. system)
//                    |
//                    -----> r
//
//
//                        4 +---------------+ 3
//                          |               |
//                          |               |
//                          |               |
//                          |       * 5     |
//                          |               |
//                          |     QUAD5     |
//                        1 +---------------+ 2
//
// Obs: 5 is an internal dof (nodeless).
//
// -------------------------------------------------------------------------
//
// $Author: evandro $
// $Revision: 1.3 $
// $Date: 1999/04/12 14:58:25 $
// $State: Exp $
//
// -------------------------------------------------------------------------

#ifndef _SHPQUAD5_H
#define _SHPQUAD5_H

#include "gbldefs.h"
#include "shpplane.h"

// -------------------------------------------------------------------------
// Quad5 (Finite) Element Shape class:
//
class cShapeQuad5 : public cPlaneShape
{
 public:
                cShapeQuad5       ( void );
  virtual      ~cShapeQuad5       ( void );
          int   GetMapOrder       ( void ) { return 1; }
          void  MapFunc           ( sNatCoord *, double * );
          void  ShapeFunc         ( sNatCoord *, double * );
          void  DerivMapRST       ( sNatCoord *, sDerivNat * );
          void  DerivShpRST       ( sNatCoord *, sDerivNat * );
          int   GetEdge           ( int *, eShapeType *, int *, int * );
          int   GetFace           ( int *, eShapeType *, int *, int * );
          void  GetNatCoordMapNode( sNatCoord * );
};

#endif

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