ANSYS螺栓法兰预紧力问题

我用ANSYS14.0做的一个 螺栓法兰预紧力的分析，模型如下
在螺栓与法兰，还有两个法兰面之间用CONTACT PAIR建立了标准的接触关系，摩擦系数0.4，然后用psmesh建立预紧面，施加预紧荷载。
finish
/clear
/filname,PY-2D
/prep7
!单位为mm，kg，s，N，Mpa
ET,1,95
MP,EX,1,2.06E5
mp,prxy,1,0.3
tb,mkin,1
tbtemp,,strain
tbdata,,0.0017,0.025,0.34
tbtemp,0.0
tbdata,,350,350,542.3
mp,ex,2,2.06e10
mp,prxy,2,0.3
mp,ex,3,2.06e5
mp,prxy,3,0.3
!柱子尺寸
a=200 !柱子宽
b=20 !柱厚度
c=26 !倒角
h=1345 !柱的高度
hh=3300!!实验段高度
!法兰板尺寸
e=320 !法兰板宽度
f=20 !法兰板厚度
!柱座尺寸
b2=20 !2段座厚20
f2=20 !2段法兰厚度为20
hzz=610 !高强螺栓柱座高度610
blc5,,,a,a
blc5,,,a-2*b,a-2*b
asba,1,2
adele,all
lfillt,1,2,c
lfillt,2,3,c
lfillt,3,4,c
lfillt,1,4,c
lfillt,5,6,c
lfillt,6,7,c
lfillt,7,8,c
lfillt,8,5,c
al,1,9,2,10,3,11,4,12
al,5,13,6,14,7,15,8,16
asba,1,2
vext,all,,,,,h-f
wpoffs,,,h-f
blc5,,,e,e
vsel,none
asel,none
!!!!!!!!!!!!!!!!!!螺栓孔
r1=28 !大螺栓孔直径
r2=24 !小螺栓孔直径
cyl4,130,65,r2/2
cyl4,65,130,r2/2
cyl4,135,,r1/2
cyl4,130,130,r1/2
cyl4,,135,r1/2
arsym,x,all
arsym,y,all
nummrg,all
numcmp,all
cm,a1,area !!!!!!!面元件a1
asel,s,loc,z,h-f
aptn,all
adele,a1
cm,afl,area !!!法兰面元件afl
asel,u,,,36
vext,all,,,,,f
wpoffs,,,f
csys,4
vsymm,z,all
vext,107,,,,,hzz/2-f2
allsel
!!!!!!!!!!!!!!!!!!!加载板
csys,0
wpcsys,0
blc5,150,,500,200,-b2
wpoffs,200
wprota,,,90
vsbw,all
allsel,all
wpcsys,0
vsel,s,loc,z,-b2,h
vptn,all
vsel,inve
vptn,all
allsel
vsel,s,loc,z,-b2,0
cm,vjzpt,volu
allsel
vsel,none
allsel,below,volu
!!!!!!!!!!!!!螺栓24*90*36*15,20*80*30*12.5
r11=24 !大螺栓直径
s11=36 !大螺栓帽
r12=20 !小螺栓直径
s12=30 !小螺栓帽
km=15 !螺栓帽厚度
ls=90 !螺栓长度
wpcsys,0
wpoffs,,,h-f-km
!!!!!!!!!!!!!!!!!!!!!!!!!!!!小螺栓
cyl4,130,65,s12/2,,,,km
cyl4,65,130,s12/2,,,,km
cyl4,135,,s11/2,,,,km
cyl4,130,130,s11/2,,,,km
cyl4,,135,s11/2,,,,km
vgen,2,all,,,,,f+f2+km
cyl4,130,65,r12/2,,,,ls
cyl4,65,130,r12/2,,,,ls
cyl4,135,,r11/2,,,,ls
cyl4,130,130,r11/2,,,,ls
cyl4,,135,r11/2,,,,ls
vsymm,x,all
vsymm,y,all
nummrg,all
numcmp,all
vptn,all
cm,vls,volu !!!!!螺栓组件
allsel
!!!!!!!!!!!!!!划分网格
vsel,u,,,vjzpt
vsel,u,,,vls
vatt,1,,1
esize,20
lesize,39,,,50
vsweep,1
allsel,all
lesize,556,,,10
vsweep,6
allsel,all
vsel,u,,,vjzpt
vsel,u,,,vls
vsel,u,,,1
vsel,r,loc,z,h+f2,h-h
esize,8
vsweep,all
allsel,all
vsel,s,,,vls
vatt,3,,1
esize,6
*do,i,57,152
vsweep,i
*enddo
allsel,all
vsel,s,,,vjzpt
vatt,2,,1
esize,30
vsweep,9
mshape,1,3d
mshkey,0
vmesh,7
allsel,all
!!!!!!!!!!!!!!接触
CM,_NODECM,NODE
CM,_ELEMCM,ELEM
CM,_KPCM,KP
CM,_LINECM,LINE
CM,_AREACM,AREA
CM,_VOLUCM,VOLU
MP,MU,1,0.4
MAT,1
R,3
REAL,3
ET,2,170
ET,3,174
KEYOPT,3,9,0
KEYOPT,3,10,2
R,3,
RMORE,
RMORE,,0
RMORE,0
ASEL,S,,,108
ASEL,A,,,126
CM,_TARGET,AREA
TYPE,2
NSLA,S,1
ESLN,S,0
ESLL,U
ESEL,U,ENAME,,188,189
NSLE,A,CT2
ESURF
CMSEL,S,_ELEMCM
ASEL,S,,,19
ASEL,A,,,38
CM,_CONTACT,AREA
TYPE,3
NSLA,S,1
ESLN,S,0
NSLE,A,CT2 ! CZMESH patch (fsk qt-40109 8/2008)
ESURF
ALLSEL
ESEL,ALL
ESEL,S,TYPE,,2
ESEL,A,TYPE,,3
ESEL,R,REAL,,3
ESEL,ALL
ESEL,S,TYPE,,2
ESEL,A,TYPE,,3
ESEL,R,REAL,,3
CMSEL,A,_NODECM
CMDEL,_NODECM
CMSEL,A,_ELEMCM
CMDEL,_ELEMCM
CMSEL,S,_KPCM
CMDEL,_KPCM
CMSEL,S,_LINECM
CMDEL,_LINECM
CMSEL,S,_AREACM
CMDEL,_AREACM
CMSEL,S,_VOLUCM
CMDEL,_VOLUCM
CMDEL,_TARGET
CMDEL,_CONTACT
vsel,s,,,vls
aslv
asel,r,loc,z,h-f
CM,_NODECM,NODE
CM,_ELEMCM,ELEM
CM,_KPCM,KP
CM,_LINECM,LINE
CM,_AREACM,AREA
CM,_VOLUCM,VOLU
MP,MU,1,0.4
MAT,1
R,4
REAL,4
ET,4,170
ET,5,174
KEYOPT,5,9,0
KEYOPT,5,10,2
R,4,
RMORE,
RMORE,,0
RMORE,0
ASEL,S,,,37
CM,_TARGET,AREA
TYPE,4
NSLA,S,1
ESLN,S,0
ESLL,U
ESEL,U,ENAME,,188,189
NSLE,A,CT2
ESURF
CMSEL,S,_ELEMCM
ASEL,S,,,626
ASEL,A,,,628
ASEL,A,,,630
ASEL,A,,,632
ASEL,A,,,634
ASEL,A,,,636
ASEL,A,,,638
ASEL,A,,,640
ASEL,A,,,642
ASEL,A,,,644
ASEL,A,,,646
ASEL,A,,,648
ASEL,A,,,650
ASEL,A,,,652
ASEL,A,,,654
ASEL,A,,,656
CM,_CONTACT,AREA
TYPE,5
NSLA,S,1
ESLN,S,0
NSLE,A,CT2 ! CZMESH patch (fsk qt-40109 8/2008)
ESURF
ALLSEL
ESEL,ALL
ESEL,S,TYPE,,4
ESEL,A,TYPE,,5
ESEL,R,REAL,,4
ESEL,ALL
ESEL,S,TYPE,,4
ESEL,A,TYPE,,5
ESEL,R,REAL,,4
CMSEL,A,_NODECM
CMDEL,_NODECM
CMSEL,A,_ELEMCM
CMDEL,_ELEMCM
CMSEL,S,_KPCM
CMDEL,_KPCM
CMSEL,S,_LINECM
CMDEL,_LINECM
CMSEL,S,_AREACM
CMDEL,_AREACM
CMSEL,S,_VOLUCM
CMDEL,_VOLUCM
CMDEL,_TARGET
CMDEL,_CONTACT
ALLSEL,ALL
vsel,s,,,vls
aslv
asel,r,loc,z,h+f2
CM,_NODECM,NODE
CM,_ELEMCM,ELEM
CM,_KPCM,KP
CM,_LINECM,LINE
CM,_AREACM,AREA
CM,_VOLUCM,VOLU
MP,MU,1,0.4
MAT,1
R,5
REAL,5
ET,6,170
ET,7,174
KEYOPT,7,9,0
KEYOPT,7,10,2
R,5,
RMORE,
RMORE,,0
RMORE,0
ASEL,S,,,125
CM,_TARGET,AREA
TYPE,6
NSLA,S,1
ESLN,S,0
ESLL,U
ESEL,U,ENAME,,188,189
NSLE,A,CT2
ESURF
CMSEL,S,_ELEMCM
ASEL,S,,,594
ASEL,A,,,596
ASEL,A,,,598
ASEL,A,,,600
ASEL,A,,,602
ASEL,A,,,604
ASEL,A,,,606
ASEL,A,,,608
ASEL,A,,,610
ASEL,A,,,612
ASEL,A,,,614
ASEL,A,,,616
ASEL,A,,,618
ASEL,A,,,620
ASEL,A,,,622
ASEL,A,,,624
CM,_CONTACT,AREA
TYPE,7
NSLA,S,1
ESLN,S,0
NSLE,A,CT2 ! CZMESH patch (fsk qt-40109 8/2008)
ESURF
ALLSEL
!!!!!!psmesh创建预紧截面
vsel,s,,,vls
mat,3
psmesh,1,yjm1,,v,59,0,z,h,,,,yj1
psmesh,2,yjm2,,v,60,0,z,h,,,,yj2
psmesh,3,yjm3,,v,61,0,z,h,,,,yj3
psmesh,4,yjm4,,v,69,0,z,h,,,,yj4
psmesh,5,yjm5,,v,70,0,z,h,,,,yj5
psmesh,6,yjm6,,v,77,0,z,h,,,,yj6
psmesh,7,yjm7,,v,78,0,z,h,,,,yj7
psmesh,8,yjm8,,v,85,0,z,h,,,,yj8
psmesh,9,yjm9,,v,57,0,z,h,,,,yj9
psmesh,10,yjm10,,v,58,0,z,h,,,,yj10
psmesh,11,yjm11,,v,67,0,z,h,,,,yj11
psmesh,12,yjm12,,v,68,0,z,h,,,,yj12
psmesh,13,yjm13,,v,75,0,z,h,,,,yj13
psmesh,14,yjm14,,v,76,0,z,h,,,,yj14
psmesh,15,yjm15,,v,83,0,z,h,,,,yj15
psmesh,16,yjm16,,v,84,0,z,h,,,,yj16
allsel,all
!!!!!!荷载和约束
/solu
csys,0
asel,s,loc,z,HH/2
da,all,symm
allsel,all
asel,s,loc,x,400
da,all,ux
da,all,uy
allsel,all
outres,all,all
antype,0
nlgeom,on
nropt,unsym
time,1
nsubst,20,10000,1
neqit,50
autots,on
solcontrol,
preten1=225000
preten2=155000
SLOAD,1,PL01,,FORC,preten1,1,2
SLOAD,2,PL01,,FORC,preten1,1,2
SLOAD,3,PL01,,FORC,preten1,1,2
SLOAD,4,PL01,,FORC,preten1,1,2
SLOAD,5,PL01,,FORC,preten1,1,2
SLOAD,6,PL01,,FORC,preten1,1,2
SLOAD,7,PL01,,FORC,preten1,1,2
SLOAD,8,PL01,,FORC,preten1,1,2
SLOAD,9,PL01,,FORC,preten2,1,2
SLOAD,10,PL01,,FORC,preten2,1,2
SLOAD,11,PL01,,FORC,preten2,1,2
SLOAD,12,PL01,,FORC,preten2,1,2
SLOAD,13,PL01,,FORC,preten2,1,2
SLOAD,14,PL01,,FORC,preten2,1,2
SLOAD,15,PL01,,FORC,preten2,1,2
SLOAD,16,PL01,,FORC,preten2,1,2
allsel,all
lswrite,1
solve
螺栓的预紧力是按规范值225KN和155KN。但是计算出来的螺栓应力达到了1000MPa。
实在是找不到办法了，求各路大神帮忙，小弟先此谢过！