DruckerPragerPotentialSurface.h

// -*-c++-*-
//----------------------------------------------------------------------------
//  XC program; finite element analysis code
//  for structural analysis and design.
//
//  Copyright (C)  Luis C. Pérez Tato
//
//  This program derives from OpenSees <http://opensees.berkeley.edu>
//  developed by the  «Pacific earthquake engineering research center».
//
//  Except for the restrictions that may arise from the copyright
//  of the original program (see copyright_opensees.txt)
//  XC is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or 
//  (at your option) any later version.
//
//  This software is distributed in the hope that it will be useful, but 
//  WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details. 
//
//
// You should have received a copy of the GNU General Public License 
// along with this program.
// If not, see <http://www.gnu.org/licenses/>.
//----------------------------------------------------------------------------
//################################################################################
//# COPYRIGHT (C):     :-))                                                    #
//# PROJECT:           Object Oriented Finite Element Program                  #
//# PURPOSE:           Drucker - Prager  potential criterion                   #
//# CLASS:             DruckerPragerPotentialSurface                                      #
//#                                                                            #
//# VERSION:                                                                   #
//# LANGUAGE:          C++.ver >= 2.0 ( Borland C++ ver=3.00, SUN C++ ver=2.1 )#
//# TARGET OS:         DOS || UNIX || . . .                                    #
//# PROGRAMMER(S):     Boris Jeremic, ZHaohui Yang                             #
//#                                                                            #
//#                                                                            #
//# DATE:              August 03 '93                                           #
//# UPDATE HISTORY:    August 08 '00                                           #
//#                                                                            #
//#                                                                            #
//#                                                                            #
//#                                                                            #
//# SHORT EXPLANATION:                                                         #
//#                                                                            #
//# if alfa1#=0 && alfa2#=0 && alfa1#=alfa2 =>                                 #
//#              Drucker-Prager with non-associated flow rule                  #
//#                                                                            #
//# if alfa1#=0 && alfa2#=0 && alfa1==alfa2 =>                                 #
//#              Drucker-Prager with associated flow rule                      #
//#                                                                            #
//# if alfa1==0 && alfa2#=0 =>                                                 #
//#              Von Mises with non-associated Drucker-Prager flow rule        #
//#                                                                            #
//# if alfa1#=0 && alfa2==0 =>                                                 #
//#              Drucker-Prager with non-associated Von Mises flow rule        #
//#                                                                            #
//# if alfa1==0 && alfa2==0 =>                                                 #
//#              Von Mises with associated flow rule                           #
//#                                                                            #
//##############################################################################
//*/

#ifndef DruckerPragerPotentialSurface_H
#define DruckerPragerPotentialSurface_H

#include "material/nD/template_3d_ep/PotentialSurface.h"

namespace XC {
class DruckerPragerPotentialSurface: public PotentialSurface
  {
  private:
    double alfa2; // potential surface orientation angle.
  public:
    DruckerPragerPotentialSurface( double a2d = 0.0 )
      : alfa2(a2d) {}   // Default constructor
    virtual ~DruckerPragerPotentialSurface()
      { }; //Virtual functions not all redefined
    PotentialSurface *getCopy(void) const; // virtual constructor.
  
    double getalfa2() const;
    void setAlfa2(const double &);

    BJtensor dQods(const EPState *EPS) const;
    BJtensor d2Qods2(const EPState *EPS) const;
    
    BJtensor d2Qodsds1(const EPState *EPS) const; // For Consistent Algorithm, Z Cheng, Jan 2004        
    
    virtual void print(std::ostream &) const;
  };

//================================================================================
// Overloaded Insertion Operator
// prints an DruckerPrager-PotentialSurface's contents 
//================================================================================
std::ostream& operator<<(std::ostream &, const DruckerPragerPotentialSurface &);

} // end of XC namespace

#endif