NineFourNodeQuadUP.h

//----------------------------------------------------------------------------
//  XC program; finite element analysis code
//  for structural analysis and design.
//
//  Copyright (C)  Luis Claudio 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/>.
//----------------------------------------------------------------------------
// Description: This file contains the class declaration for                 //
// NineFourNodeQuadUP, a 9-4-node (9 node for solid and 4 node for fluid) //
// plane strain element for solid-fluid fully coupled analysis. This         //
// implementation is a simplified u-p formulation of Biot theory             //
// (u - solid displacement, p - fluid pressure). Each element node has two   //
// DOFs for u and 1 DOF for p.                                               //
//                                                                           //
// Written by Zhaohui Yang  (March 2004)                                     //
//                                                                           //

// $Revision: 1.1 $
// $Date: 2005/09/22 21:28:36 $
// $Source: /usr/local/cvs/OpenSees/SRC/element/UP-ucsd/Nine_Four_Node_QuadUP.h,v $

#ifndef NineFourNodeQuadUP_h
#define NineFourNodeQuadUP_h

#include <domain/mesh/element/ElemWithMaterial.h>
#include <utility/matrix/Matrix.h>
#include <utility/matrix/Vector.h>
#include "domain/mesh/element/utils/physical_properties/SolidMech2D.h"
#include "domain/mesh/element/utils/body_forces/BodyForces2D.h"

namespace XC {
class Node;
class NDMaterial;
class Response;

//
class NineFourNodeQuadUP: public ElemWithMaterial<9,SolidMech2D>
  {
  private:
    BodyForces2D bf; 
    mutable Matrix *Ki;

    double kc;   // combined bulk modulus
    double perm[2];  // lateral/vertical permeability

    static Matrix K;        // Element stiffness, damping, and mass Matrix
    static Vector P;        // Element resisting force vector
    static const int nintu;
    static const int nintp;
    static const int nenu;
    static const int nenp;

    static double shgu[3][9][9];    // Stores shape functions and derivatives (overwritten)
    static double shgp[3][4][4];    // Stores shape functions and derivatives (overwritten)
    static double shgq[3][9][4];    // Stores shape functions and derivatives (overwritten)
    static double shlu[3][9][9];    // Stores shape functions and derivatives
    static double shlp[3][4][4];    // Stores shape functions and derivatives
    static double shlq[3][9][4];    // Stores shape functions and derivatives
    static double wu[9];        // Stores quadrature weights
    static double wp[4];        // Stores quadrature weights
    static double dvolu[9];  // Stores detJacobian (overwritten)
    static double dvolp[4];  // Stores detJacobian (overwritten)
    static double dvolq[4];  // Stores detJacobian (overwritten)

    // private member functions - only objects of this class can call these
    double mixtureRho(int ipt) const;  // Mixture mass density at integration point i
    void shapeFunction(double *w, int nint, int nen, int mode) const;
    void globalShapeFunction(double *dvol, double *w, int nint, int nen, int mode) const;
  protected:
    int sendData(CommParameters &);
    int recvData(const CommParameters &);
  public:
    NineFourNodeQuadUP(int tag, int nd1, int nd2, int nd3, int nd4,
          int nd5, int nd6, int nd7, int nd8, int nd9,
          NDMaterial &m, const char *type,
          double t, double bulk, double rhof, double perm1, double perm2,
          const BodyForces2D &bForces= BodyForces2D());
    NineFourNodeQuadUP(void);
    Element *getCopy(void) const;    
    virtual ~NineFourNodeQuadUP();

    int getNumDOF(void) const;
    void setDomain(Domain *theDomain);

    // public methods to set the state of the element
    int update(void);

    // public methods to obtain stiffness, mass, damping and residual information
    const Matrix &getTangentStiff(void) const;
    const Matrix &getInitialStiff(void) const;
    const Matrix &getDamp(void) const;
    const Matrix &getMass(void) const;

    int addLoad(ElementalLoad *theLoad, double loadFactor);
    int addInertiaLoadToUnbalance(const Vector &accel);
    const Vector &getResistingForce(void) const;
    const Vector &getResistingForceIncInertia(void) const;

    // public methods for element output
    int sendSelf(CommParameters &);
    int recvSelf(const CommParameters &);
    void Print(std::ostream &s, int flag =0);

    Response *setResponse(const std::vector<std::string> &argv, Information &eleInformation);
    int getResponse(int responseID, Information &eleInformation);

    int setParameter(const std::vector<std::string> &argv, Parameter &param);
    int updateParameter(int parameterID, Information &info);

    // RWB; PyLiq1 & TzLiq1 need to see the excess pore pressure and initial stresses.
    friend class PyLiq1;
    friend class TzLiq1;
  };
} // end of XC namespace

#endif