Deformable indenter

In this example a half cylindrical indenter is pushed into a block of material. The example illustrates the use of super nodes and blending to define the indenter and the contact surface. Node to surface contact is used with augmentation.

feap    ** Contact Example of a deformable indenter into a block **
0 0 0 2 2 4

mate 1  ! Indenter material
 solid
  plane strain 
   elastic isotropic 210e5 0.3
   finite

mate 2    ! Material being tested
 solid 
 plane strain
 elast isot 210e3 0.3
 finite

para
 r = 20.0	!ball radius
 w = 40          !block depth
 h = w/2+r       !height of the half-cylinder
 L = 100         !block length
 n = 10          !mesh density indenter must be even
 m = 15          !mesh density tested material
 d = -.1         !displacement of indenter

! tested material block
block 1        
 cart 3*m m 
 mate 2
  1 -L/2 -w/2
  2  L/2 -w/2
  3  L/2  w/2
  4 -L/2  w/2

ebou add
 2 -w/2 0 1
 1 -L/2 1 0

! indentor using super nodes and blending
snode
  1     -r                            h
  2 -0.4*r                            h
  3  0.4*r                            h
  4      r                            h
  5 -0.5*r/sqrt(2.0) -0.5*r/sqrt(2.0)+h
  6    0.0                     -0.5*r+h
  7 +0.5*r/sqrt(2.0) -0.5*r/sqrt(2.0)+h
  8     -r/sqrt(2.0)     -r/sqrt(2.0)+h
  9    0.0                         -r+h
 10      r/sqrt(2.0)     -r/sqrt(2.0)+h
 11    0.0                            h

side
 segm 5 n/2 6 n/2 7
 pola 1  8 11
 pola 8  9 11
 pola 9 10 11
 pola 10 4 11

blend           ! Center of indenter
 surface n n
 mate 1
  5 7 3 2

blend           ! Outer 1/4 of indenter
 surface n/2 n/2
 mate 1
  2 1 8 5

blend           ! Outer 1/4 of indenter
 surface n/2 n/2
 mate 1
  5 8 9 6

blend           ! Outer 1/4 of indenter
 surface n/2 n/2
 mate 1
  6 9 10 7

blend           ! Outer 1/4 of indenter
 surface n/2 n/2
 mate 1
  10 4 3 7

eboun
 2 h 1 1

edisp
 2 h 0 d

end

tie mate 1 1  ! Tie the indenter together

contact
 surf 1
  line
   blend segm 
   polar 1 4 11

 surf 2
  line
  block segm
  1  L/2 w/2
  2 -L/2 w/2

 mate 1
  standard
  fric coul 0.5

 pair 1
  ntos 1 2
  solm penalty 1e7 1e4
  augm
  mate,,1
  tole,,1e-8 1e-8 1e-8
        ! blank line needed
end ! End contact

 
batch
 dt,,.1
 prop
 plot defo               
end


batch
 loop time 10
  cont check
  time
  LOOP,augment,4
   LOOP,newton,30	
    utang,,1
   NEXT Newton
   AUGMent
  NEXT AUGMent
  plot wipe	
  plot mesh
  plot,cont,2
  plot,reac
 next time
end


inte

stop