contactmat.cpp

Finite element program for mechanical problem. It can solve various problem in solid problem

#include "contactmat.h"
#include "matrix.h"
#include "vector.h"
#include "stochdriver.h"
#include "global.h"
#include "intpoints.h"

contactmat::contactmat (void)
{
  slip = 0.0;  normal = 0.0;  limitn=0.0;  limits=0.0;
}
contactmat::~contactmat (void)
{

}

void contactmat::read (XFILE *in)
{
  xfscanf (in,"%lf %lf %lf %lf",&slip,&normal,&limits,&limitn);
}

/**
   function returns stiffness %matrix of material
   
   @param d - stiffness %matrix of the material

   JK, 11.6.2006
*/
void contactmat::matstiff (matrix &d,long ipp)
{
  long i,n = Mm->ip[ipp].ncompstr;
  vector eps(n),sig(n);

  //  initial values
  for (i=0;i<n;i++){
    eps[i]=Mm->ip[ipp].strain[i];
  }
  
  sig[0]=eps[0]*normal;
  if (sig[0]>limitn)
    d[0][0]=limitn;
  else
    d[0][0]=normal;

  sig[1]=eps[1]*slip;
  if (sig[1]>limits)
    d[1][1]=limits;
  else
    d[1][1]=slip;
}


/**
   function computes nodal forces in contact problems
   nodal forces are computed from difference of nodal displacements
   at appropriate nodes
   the name nlstresses is used only with respect to other
   "classical" material models which work with stresses
   
   @param ipp - integration point id
   
   JK, 11.6.2006
*/
void contactmat::nlstresses (long ipp)
{
  long i, n = Mm->ip[ipp].ncompstr;
  vector eps(n),sig(n);
  
  //  initial values
  for (i=0;i<n;i++){
    eps[i]=Mm->ip[ipp].strain[i];
  }
  
  sig[0]=eps[0]*normal;
  if (sig[0]>limitn)
    sig[0]=limitn;
  sig[1]=eps[1]*slip;
  if (sig[1]>limits)
    sig[1]=limits;
  
  for (i=0;i<n;i++){
    Mm->ip[ipp].stress[i]=sig[i];
  }
  
}

void contactmat::changeparam (atsel &atm,vector &val)
{
  long i;
  
  for (i=0;i<atm.num;i++){
    switch (atm.atrib[i]){
    case 0:{
      slip=val[i];
      break;
    }
    case 1:{
      normal=val[i];
      break;
    }
    default:{
      fprintf (stderr,"\n\n wrong number of atribute in function changeparam (%s, line %d).\n",__FILE__,__LINE__);
    }
    }
  }
}