A nonlinear static analysis is performed in two load steps. Geometric nonlinearity is included in the analysis, and automatic time increments are used. An unsymmetric solver is used due to the presence of friction. For the first load step when wear is not active, a larger time step is used.

/solu
! choose here
antype,4                   ! static analysis
timint,off
nlgeom,on                  ! Turn on Large Deformation Effects
_thickRatio=  1            ! Ratio of thick parts in the model
eqsl,sparse,,,,,1
nropt,unsym                ! Use full Newton-Raphson with unsymmetric matrices
cntr,print,1               ! print out contact info and also make no initial contact an error
dmpoption,emat,no          ! Don't combine emat file for DANSYS
dmpoption,esav,no          ! Don't combine esav file for DANSYS
nldiag,cont,subs           ! print out contact info each substeps
rescontrol,define,last,last,,dele          ! Program Controlled
/com,****************************************************
/com,******************* SOLVE FOR LS 1 OF 2 ****************
!Applying the pretention load
*if,dirld,eq,1,then
  d,_npilot101,ux,%_loadvariu%
  d,_npilot101,uy,0
  d,_npilot,uz,0
*elseif,dirld,eq,2,then
  d,_npilot101,ux,0
  d,_npilot101,uy,%_loadvariu%
  d,_npilot,uz,0
*else
  d,_npilot101,ux,0
  d,_npilot,uy,0
  d,_npilot101,uz,%_loadvariu%
*endif

d,_npilot101,rotx,0
d,_npilot101,roty,0
d,_npilot101,rotz,0

f,_nbolt115,fx,36605.
time,1
autots,on                   ! User turned on automatic time stepping
deltim,(tim1/20.0),(tim1/50.0),(tim1/10),OFF
outres,erase
outres,all,none
outres,nsol,all,
outres,rsol,all
outres,eangl,all
outres,etmp,all
outres,veng,all
outres,strs,all,
outres,epel,all,
outres,eppl,all,
outres,cont,all,
nldiag,cont,subs
!resultant force at the bolt shank
nlhist,pair,bltshnk_CFNX,cont,CFNX,20
nlhist,pair,bltshnk_CFNY,cont,CFNY,20
nlhist,pair,bltshnk_CFNZ,cont,CFNZ,20
nlhist,pair,bltshnk_CFSX,cont,CFSX,20
nlhist,pair,bltshnk_CFSY,cont,CFSY,20
nlhist,pair,bltshnk_CFSZ,cont,CFSZ,20
!contact forces due pressure and shear stress distribution at 
!resultant force at the bolt-nut interface
nlhist,pair,blt_nut_CFNX,cont,CFNX,18
nlhist,pair,blt_nut_CFNY,cont,CFNY,18
nlhist,pair,blt_nut_CFNZ,cont,CFNZ,18
nlhist,pair,blt_nut_CFSX,cont,CFSX,18
nlhist,pair,blt_nut_CFSY,cont,CFSY,18
nlhist,pair,blt_nut_CFSZ,cont,CFSZ,18
!contacting area and volume wear at wearing  contact pairs
nlhist,pair,plt1_plt2_carea,cont,carea,8
nlhist,pair,plt1_wsr1_carea,cont,carea,10
nlhist,pair,bolt_wsr1_carea,cont,carea,12
nlhist,pair,plt2_wsr2_carea,cont,carea,14
nlhist,pair,nut_wsr1_carea,cont,carea,16
nlhist,pair,blt_nut_carea,cont,carea,18
nlhist,pair,plt1_plt2_vwear1,cont,wear,8
nlhist,pair,plt1_plt2_vwear2,cont,wear,9
nlhist,pair,plt1_wsr1_vwear1,cont,wear,10
nlhist,pair,plt1_wsr1_vwear2,cont,wear,11
nlhist,pair,bolt_wsr1_vwear1,cont,wear,12
nlhist,pair,bolt_wsr1_vwear2,cont,wear,13
nlhist,pair,plt2_wsr2_vwear1,cont,wear,14
nlhist,pair,plt2_wsr2_vwear2,cont,wear,15
nlhist,pair,nut_wsr1_vwear1,cont,wear,16
nlhist,pair,nut_wsr1_vwear2,cont,wear,17
nlhist,pair,blt_nut_vwear1,cont,wear,18
!plastic strain at the bolt shank
el_egnpl = 79024
nd_egnpl = 92647
nlhist,esol,plst_strain_1,eppl,1,nd_egnpl,el_egnpl
nlhist,esol,plst_strain_2,eppl,2,nd_egnpl,el_egnpl
nlhist,esol,plst_strain_3,eppl,3,nd_egnpl,el_egnpl
solve 
/com ****************************************************
/com *************** FINISHED SOLVE FOR LS 1 *************
/com ****************************************************
/com ******************* SOLVE FOR LS 2 OF 2 ****************
!Applying the cyclic load
timint,on
tintp,mosp
allsel,all
fdel,_nbolt115,all
d,_nbolt115,ux,%_FIX%
autots,on         ! User turned on automatic time stepping
deltim,0.02*timp,0.01*timp,0.04*tmp,OFF
time, tim1+6.0*timp
frqout= 1 ! write data at each  substeps
outres,erase
outres,all,none
outres,nsol,frqout,
outres,rsol,frqout,
outres,eangl,frqout,
outres,etmp,frqout
outres,veng,frqout
outres,strs,frqout,
outres,epel,frqout,
outres,eppl,frqout,
outres,cont,frqout,
solve