libeam2d.C

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/*
 *
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 *               ##   ##  ##   ##  ##      ##      ## ### ##
 *              ##   ##  ##   ##  ####    ####    ##  #  ##
 *             ##   ##  ##   ##  ##      ##      ##     ##
 *            ##   ##  ##   ##  ##      ##      ##     ##
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 *
 *
 *             OOFEM : Object Oriented Finite Element Code
 *
 *               Copyright (C) 1993 - 2013   Borek Patzak
 *
 *
 *
 *       Czech Technical University, Faculty of Civil Engineering,
 *   Department of Structural Mechanics, 166 29 Prague, Czech Republic
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This program 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "../sm/Elements/Beams/libeam2d.h"
#include "../sm/Materials/structuralms.h"
#include "fei2dlinelin.h"
#include "node.h"
#include "material.h"
#include "crosssection.h"
#include "gausspoint.h"
#include "gaussintegrationrule.h"
#include "floatmatrix.h"
#include "intarray.h"
#include "floatarray.h"
#include "mathfem.h"
#include "classfactory.h"

namespace oofem {
REGISTER_Element(LIBeam2d);

// Set up interpolation coordinates
FEI2dLineLin LIBeam2d :: interpolation(1, 3);

LIBeam2d :: LIBeam2d(int n, Domain *aDomain) : StructuralElement(n, aDomain), LayeredCrossSectionInterface()
{
    numberOfDofMans     = 2;
    length              = 0.;
    pitch               = 10.;   // a dummy value
}


FEInterpolation *LIBeam2d :: giveInterpolation() const { return & interpolation; }


Interface *
LIBeam2d :: giveInterface(InterfaceType interface)
{
    if ( interface == LayeredCrossSectionInterfaceType ) {
        return static_cast< LayeredCrossSectionInterface * >(this);
    }

    return NULL;
}


void
LIBeam2d :: computeBmatrixAt(GaussPoint *gp, FloatMatrix &answer, int li, int ui)
// Returns the strain matrix of the receiver.
{
    double l, ksi, n1x, n4x, n3xx, n6xx, n2xxx, n3xxx, n5xxx, n6xxx;

    l    = this->computeLength();
    ksi  = gp->giveNaturalCoordinate(1);
    n1x   = -1.0 / l;
    n4x   =  1.0 / l;
    n3xx  = -1.0 / l;
    n6xx  =  1.0 / l;
    n2xxx = -1.0 / l;
    n3xxx =  0.5 * ( 1 - ksi );
    n5xxx =  1.0 / l;
    n6xxx =  0.5 * ( 1. + ksi );

    answer.resize(3, 6);
    answer.zero();

    answer.at(1, 1) =  n1x;
    answer.at(1, 4) =  n4x;
    answer.at(2, 3) =  n3xx;
    answer.at(2, 6) =  n6xx;
    answer.at(3, 2) =  n2xxx;
    answer.at(3, 3) =  n3xxx;
    answer.at(3, 5) =  n5xxx;
    answer.at(3, 6) =  n6xxx;
}


void
LIBeam2d :: computeGaussPoints()
// Sets up the array of Gauss Points of the receiver.
{
    if ( integrationRulesArray.size() == 0 ) {
        integrationRulesArray.resize( 1 );
        integrationRulesArray [ 0 ].reset( new GaussIntegrationRule(1, this, 1, 2) );
        this->giveCrossSection()->setupIntegrationPoints(* integrationRulesArray [ 0 ], 1, this);
    }
}


void
LIBeam2d :: computeConstitutiveMatrixAt(FloatMatrix &answer, MatResponseMode rMode, GaussPoint *gp, TimeStep *tStep)
{
    this->giveStructuralCrossSection()->give2dBeamStiffMtrx(answer, rMode, gp, tStep);
}


void
LIBeam2d :: computeStressVector(FloatArray &answer, const FloatArray &strain, GaussPoint *gp, TimeStep *tStep)
{
    this->giveStructuralCrossSection()->giveGeneralizedStress_Beam2d(answer, gp, strain, tStep);
}


int
LIBeam2d :: computeGlobalCoordinates(FloatArray &answer, const FloatArray &lcoords)
{
    double ksi, n1, n2;

    ksi = lcoords.at(1);
    n1  = ( 1. - ksi ) * 0.5;
    n2  = ( 1. + ksi ) * 0.5;

    answer.resize(3);
    answer.at(1) = n1 * this->giveNode(1)->giveCoordinate(1) + n2 *this->giveNode(2)->giveCoordinate(1);
    answer.at(3) = n1 * this->giveNode(1)->giveCoordinate(3) + n2 *this->giveNode(2)->giveCoordinate(3);

    return 1;
}


void
LIBeam2d :: computeLumpedMassMatrix(FloatMatrix &answer, TimeStep *tStep)
// Returns the lumped mass matrix of the receiver. This expression is
// valid in both local and global axes.
{
    GaussPoint *gp = integrationRulesArray [ 0 ]->getIntegrationPoint(0);
    double density = this->giveStructuralCrossSection()->give('d', gp);
    double halfMass = density * this->giveCrossSection()->give(CS_Area, gp) * this->computeLength() / 2.;
    answer.resize(6, 6);
    answer.zero();
    answer.at(1, 1) = halfMass;
    answer.at(2, 2) = halfMass;
    answer.at(4, 4) = halfMass;
    answer.at(5, 5) = halfMass;
}


void
LIBeam2d :: computeNmatrixAt(const FloatArray &iLocCoord, FloatMatrix &answer)
// Returns the displacement interpolation matrix {N} of the receiver, eva-
// luated at gp.
{
    double ksi, n1, n2;

    ksi = iLocCoord.at(1);
    n1  = ( 1. - ksi ) * 0.5;
    n2  = ( 1. + ksi ) * 0.5;

    answer.resize(3, 6);
    answer.zero();

    answer.at(1, 1) = n1;
    answer.at(1, 4) = n2;
    answer.at(2, 2) = n1;
    answer.at(2, 5) = n2;
    answer.at(3, 3) = n1;
    answer.at(3, 6) = n2;
}


void
LIBeam2d :: computeStiffnessMatrix(FloatMatrix &answer, MatResponseMode rMode, TimeStep *tStep)
// Returns the stiffness matrix of the receiver, expressed in the global
// axes.
{
    StructuralElement :: computeStiffnessMatrix(answer, rMode, tStep);
}


bool
LIBeam2d :: computeGtoLRotationMatrix(FloatMatrix &answer)
{
    double sine, cosine;

    sine = sin( this->givePitch() );
    cosine = cos(pitch);

    answer.resize(6, 6);
    answer.zero();

    answer.at(1, 1) =  cosine;
    answer.at(1, 2) =  sine;
    answer.at(2, 1) = -sine;
    answer.at(2, 2) =  cosine;
    answer.at(3, 3) =  1.;
    answer.at(4, 4) =  cosine;
    answer.at(4, 5) =  sine;
    answer.at(5, 4) = -sine;
    answer.at(5, 5) =  cosine;
    answer.at(6, 6) =  1.;

    return true;
}


double
LIBeam2d :: computeVolumeAround(GaussPoint *gp)
// Returns the length of the receiver. This method is valid only if 1
// Gauss point is used.
{
    double weight  = gp->giveWeight();
    return weight * 0.5 * this->computeLength();
}


void
LIBeam2d :: computeStrainVectorInLayer(FloatArray &answer, const FloatArray &masterGpStrain, GaussPoint *masterGp, GaussPoint *slaveGp, TimeStep *tStep)
//
// returns full 3d strain vector of given layer (whose z-coordinate from center-line is
// stored in slaveGp) for given tStep
//
{
    double layerZeta, layerZCoord, top, bottom;

    top    = this->giveCrossSection()->give(CS_TopZCoord, masterGp);
    bottom = this->giveCrossSection()->give(CS_BottomZCoord, masterGp);
    layerZeta = slaveGp->giveNaturalCoordinate(3);
    layerZCoord = 0.5 * ( ( 1. - layerZeta ) * bottom + ( 1. + layerZeta ) * top );

    answer.resize(2); // {Exx,GMzx}

    answer.at(1) = masterGpStrain.at(1) + masterGpStrain.at(2) * layerZCoord;
    answer.at(2) = masterGpStrain.at(3);
}


int
LIBeam2d :: giveIPValue(FloatArray &answer, GaussPoint *gp, InternalStateType type, TimeStep *tStep)
{
    if ( type == IST_BeamForceMomentTensor ) {
        answer = static_cast< StructuralMaterialStatus * >( gp->giveMaterialStatus() )->giveStressVector();
        return 1;
    } else if ( type == IST_BeamStrainCurvatureTensor ) {
        answer = static_cast< StructuralMaterialStatus * >( gp->giveMaterialStatus() )->giveStrainVector();
        return 1;
    } else {
        return StructuralElement :: giveIPValue(answer, gp, type, tStep);
    }
}


void
LIBeam2d :: giveDofManDofIDMask(int inode, IntArray &answer) const
{
    answer = {D_u, D_w, R_v};
}


double
LIBeam2d :: computeLength()
// Returns the length of the receiver.
{
    double dx, dy;
    Node *nodeA, *nodeB;

    if ( length == 0. ) {
        nodeA   = this->giveNode(1);
        nodeB   = this->giveNode(2);
        dx      = nodeB->giveCoordinate(1) - nodeA->giveCoordinate(1);
        dy      = nodeB->giveCoordinate(3) - nodeA->giveCoordinate(3);
        length  = sqrt(dx * dx + dy * dy);
    }

    return length;
}


double
LIBeam2d :: givePitch()
// Returns the pitch of the receiver.
{
    double xA, xB, yA, yB;
    Node *nodeA, *nodeB;

    if ( pitch == 10. ) {             // 10. : dummy initialization value
        nodeA  = this->giveNode(1);
        nodeB  = this->giveNode(2);
        xA     = nodeA->giveCoordinate(1);
        xB     = nodeB->giveCoordinate(1);
        yA     = nodeA->giveCoordinate(3);
        yB     = nodeB->giveCoordinate(3);
        pitch  = atan2(yB - yA, xB - xA);
    }

    return pitch;
}


IRResultType
LIBeam2d :: initializeFrom(InputRecord *ir)
{
    return StructuralElement :: initializeFrom(ir);
}



void
LIBeam2d :: giveEdgeDofMapping(IntArray &answer, int iEdge) const
{
    /*
     * provides dof mapping of local edge dofs (only nonzero are taken into account)
     * to global element dofs
     */

    if ( iEdge != 1 ) {
        OOFEM_ERROR("wrong edge number");
    }

    answer.resize(6);
    answer.at(1) = 1;
    answer.at(2) = 2;
    answer.at(3) = 3;
    answer.at(4) = 4;
    answer.at(5) = 5;
    answer.at(6) = 6;
}


double
LIBeam2d :: computeEdgeVolumeAround(GaussPoint *gp, int iEdge)
{
    if ( iEdge != 1 ) { // edge between nodes 1 2
        OOFEM_ERROR("wrong egde number");
    }

    double weight  = gp->giveWeight();
    return 0.5 * this->computeLength() * weight;
}


void
LIBeam2d :: computeBodyLoadVectorAt(FloatArray &answer, Load *load, TimeStep *tStep, ValueModeType mode)
{
    FloatArray lc(1);
    StructuralElement :: computeBodyLoadVectorAt(answer, load, tStep, mode);
    answer.times( this->giveCrossSection()->give(CS_Area, lc, this) );
}


int
LIBeam2d :: computeLoadGToLRotationMtrx(FloatMatrix &answer)
{
    /*
     * Returns transformation matrix from global coordinate system to local
     * element coordinate system for element load vector components.
     * If no transformation is necessary, answer is empty matrix (default);
     */

    // f(elemLocal) = T * f (global)

    double sine, cosine;

    answer.resize(3, 3);
    answer.zero();

    sine = sin( this->givePitch() );
    cosine = cos(pitch);

    answer.at(1, 1) = cosine;
    answer.at(1, 2) = -sine;
    answer.at(2, 1) = sine;
    answer.at(2, 2) = cosine;
    answer.at(3, 3) = 1.0;

    return 1;
}


int
LIBeam2d :: computeLoadLEToLRotationMatrix(FloatMatrix &answer, int iEdge, GaussPoint *gp)
{
    // returns transformation matrix from
    // edge local coordinate system
    // to element local c.s
    // (same as global c.s in this case)
    //
    // i.e. f(element local) = T * f(edge local)
    //
    answer.clear();
    return 0;
}
} // end namespace oofem