Method getNd2

SRC/element/mixedBeamColumn/MixedBeamColumn2d.cpp:1620–1636

}

Matrix
MixedBeamColumn2d::getNd2(int sec, double P, double L){
   double xi[MAX_NUM_SECTIONS];
   beamIntegr->getSectionLocations(numSections, L, xi);

   double x, A, B;

   x = L * xi[sec];
   A = L * ( x / L - 2 * pow( x / L, 2 ) + pow( x / L, 3 ) );
   B = L * ( -pow( x / L, 2 ) + pow( x / L, 3 ) );

   theSectionNaturalMatrix.Zero();
   theSectionNaturalMatrix(1,1) = P * A;
   theSectionNaturalMatrix(1,2) = P * B;

   return theSectionNaturalMatrix;
}


Matrix