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3. S
tres
s A
naly
sis
Stre
ss A
naly
sis
Ove
rvie
w
�St
ress
ana
lysi
sis
a g
ener
al te
rm u
sed
to d
escr
ibe
anal
yses
w
here
the
resu
lts q
uant
ities
incl
ude
stre
sses
and
str
ains
. It
is a
lso
know
n as
str
uctu
ral a
naly
sis.
�A
s de
scrib
ed in
Cha
pter
2, A
NSY
S al
low
s se
vera
l typ
es o
f st
ress
ana
lyse
s:St
atic
Tran
sien
t Dyn
amic
Mod
alSp
ectr
umH
arm
onic
Expl
icit
Dyn
amic
s
�In
this
cha
pter
, we
will
use
a li
near
sta
tic a
naly
sis
to d
escr
ibe
the
step
s in
volv
ed in
an
anal
ysis
. B
y m
aste
ring
thes
e st
eps,
yo
u ca
n qu
ickl
y le
arn
how
to d
o ot
her a
naly
ses.
Stre
ss A
naly
sis
...O
verv
iew
�To
pics
cov
ered
:A
. A
naly
sis
Step
sB
. G
eom
etry
C.
Mes
hing
D.
Load
ing
E. S
olve
F. R
evie
win
g R
esul
tsG
. C
heck
ing
Valid
ity o
f Sol
utio
nH
. W
orks
hop
Stre
ss A
naly
sis
A.
Ana
lysi
s St
eps
Ever
y an
alys
is in
volv
es th
ree
mai
n st
eps:
�Pr
epro
cess
ing
�C
reat
e or
impo
rt th
e m
odel
geo
met
ry�
Mes
h th
e ge
omet
ry
�So
lutio
n�
App
ly lo
ads
�So
lve
�Po
stpr
oces
sing
�R
evie
w re
sults
�C
heck
the
valid
ity o
f the
sol
utio
n
Prep
roce
ssin
g
Solu
tion
Post
proc
essi
ng
Stre
ss A
naly
sis
...A
naly
sis
Step
s
�N
otic
e th
at th
e A
NSY
S M
ain
Men
u is
als
o or
gani
zed
in te
rms
of p
repr
oces
sing
, sol
utio
n, a
nd p
ostp
roce
ssin
g.
Stre
ss A
naly
sis
...A
naly
sis
Step
s
�Th
e pr
epro
cess
or (c
alle
d PR
EP7
in A
NSY
S) is
whe
re y
ou
prov
ide
the
maj
ority
of t
he in
putt
o th
e pr
ogra
m.
�Its
mai
n pu
rpos
e is
to g
ener
ate
the
finite
ele
men
t mod
el,
whi
ch c
onsi
sts
mai
nly
of n
odes
, ele
men
ts, a
nd m
ater
ial
prop
erty
def
initi
ons.
You
can
als
o us
e PR
EP7
to a
pply
load
s.
�U
sual
ly b
egin
s w
ith d
efin
ition
of t
he m
odel
geo
met
ry.
�A
sol
id m
odel
mod
el is
typi
cally
use
d to
repr
esen
t mod
el
geom
etry
.�
A C
AD
-type
mat
hem
atic
al re
pres
enta
tion
that
def
ines
the
geom
etry
of t
he s
truc
ture
.�
May
con
sist
of s
olid
s or
just
sur
face
s, d
epen
ding
on
wha
t is
bein
g m
odel
ed.
�A
typi
cal s
olid
mod
el is
def
ined
by
volu
mes
, are
as, l
ines
, and
keyp
oint
s.�
Volu
mes
are
boun
ded
by a
reas
. Th
ey re
pres
ent s
olid
obj
ects
.�
Are
asar
e bo
unde
d by
line
s. T
hey
repr
esen
t fac
es o
f sol
id
obje
cts,
or p
lana
r or s
hell
obje
cts.
�Li
nes
are
boun
ded
byke
ypoi
nts.
The
y re
pres
ent e
dges
of
obje
cts.
�K
eypo
ints
are
loca
tions
in 3
-D s
pace
. Th
ey re
pres
ent v
ertic
es o
f ob
ject
s.
Volu
mes
Area
sLi
nes
&Ke
ypoi
nts
Stre
ss A
naly
sis
-Pr
epro
cess
ing
B.
Geo
met
ry
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...G
eom
etry
�Th
ere
is a
bui
lt-in
hie
rarc
hyam
ong
solid
mod
el
entit
ies.
Key
poin
tsar
e th
e �f
ound
atio
n� e
ntiti
es.
Line
s ar
e �b
uilt�
from
the
keyp
oint
s, a
reas
from
lin
es, a
nd v
olum
es fr
om a
reas
.
�Th
is h
iera
rchy
hol
ds tr
ue re
gard
less
of h
ow th
e so
lid m
odel
is c
reat
ed.
Key
poin
ts
Line
s
Are
as
Volu
mes
I�ll
just
chan
geth
is li
neLi
nes
Key
poin
ts
Areas
Volumes
OO
Ps!
�A
NSY
S w
ill n
ot a
llow
you
to d
elet
e or
mod
ify a
low
er-o
rder
en
tity
if it
is a
ttach
ed to
a h
ighe
r-or
der e
ntity
. (C
erta
in ty
pes
of m
odifi
catio
ns a
re a
llow
ed�
dis
cuss
ed la
ter.)
Key
poin
ts
Line
s
Are
as
Volu
mes
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...G
eom
etry
�Yo
u ca
n ei
ther
cre
ate
a so
lid m
odel
in A
NSY
S or
impo
rtit
from
ano
ther
sof
twar
e pa
ckag
e.
�D
etai
ls o
f bot
h m
etho
ds w
ill b
e pr
esen
ted
late
r. F
or n
ow, w
e w
ill b
riefly
dis
cuss
how
to im
port
an
IGES
file
and
sca
le th
e ge
omet
ry if
nee
ded.
�IG
ES (I
nitia
l Gra
phic
s Ex
chan
ge S
peci
ficat
ion)
is a
way
to
tran
sfer
sol
id m
odel
geo
met
ry fr
om o
ne s
oftw
are
pack
age
to
anot
her.
�A
n IG
ES fi
le is
ASC
II, a
llow
ing
it to
be
easi
ly tr
ansp
orte
d be
twee
n co
mpu
ter s
yste
ms.
�M
ost p
acka
ges,
incl
udin
g A
NSY
S, a
llow
you
to w
rite
as w
ell a
s re
adan
IGES
file
.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...G
eom
etry
�To
impo
rt a
n IG
ES fi
le in
to A
NSY
S:�
Util
ity M
enu
> Fi
le >
Impo
rt >
IGES
...�
In th
e re
sulti
ng d
ialo
g bo
x, c
hoos
e th
e al
tern
ate
met
hod*
(Alte
node
feat
ur) a
nd
pres
s O
K (d
efau
lts fo
r eve
ryth
ing
else
).�
In th
e se
cond
dia
log
box,
cho
ose
the
desi
red
file
and
pres
s O
K.
�O
R u
se th
e IG
ESIN
com
man
d:�
/aux
15�
iopt
n,ig
es,a
lte�
iges
in,filename,extension,directory
�fin
ish
*Det
ails
abo
ut th
e de
faul
t vs.
alte
rnat
e m
etho
d an
d th
e ot
her o
ptio
ns w
ill b
e pr
esen
ted
late
r.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...G
eom
etry
�W
hen
the
impo
rt is
com
plet
ed, A
NSY
S w
ill a
utom
atic
ally
plo
t th
e ge
omet
ry.
�Yo
u m
ay th
en m
odify
the
geom
etry
as
need
ed.
�A
NSY
S al
low
s m
any
oper
atio
ns o
n th
e so
lid
mod
el, w
hich
we
will
de
scrib
e la
ter.
�Fo
r now
, we
will
dis
cuss
ho
w to
sca
leth
e m
odel
to a
di
ffere
nt s
et o
f uni
ts.
(Not
e:
Scal
ing
is N
OT
avai
labl
e fo
r a
defa
ultI
GES
impo
rt.)
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...G
eom
etry
�Sc
alin
g is
typi
cally
nee
ded
whe
n yo
u w
ant t
o co
nver
t the
geo
met
ry
to a
diff
eren
t set
of u
nits
, say
from
inch
es to
mill
imet
ers.
�To
sca
le a
mod
el in
AN
SYS:
�Fi
rst s
ave
the
data
base
--To
olba
r >
SAVE
_DB
orSA
VE c
omm
and.
�Th
en M
ain
Men
u >
Prep
roce
ssor
>
Ope
rate
> S
cale
> V
olum
es (
choo
se th
e hi
ghes
t-lev
el e
ntity
ava
ilabl
e in
the
mod
el)
�[P
ick
All]
to p
ick
all v
olum
es�
Then
ent
er d
esire
d sc
ale
fact
ors
for R
X, R
Y, R
Z an
d se
t IM
OVE
to
�Mov
ed�
inst
ead
of �
Cop
ied�
�O
r use
the
VLSC
ALE
com
man
d:�
vlsc
ale,
all,,
,25.
4,25
.4,2
5.4,
,,1
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...G
eom
etry
�Pr
epro
cess
ing
!G
eom
etry
�M
eshi
ng
�So
lutio
n�
Load
ing
�So
lve
�Po
stpr
oces
sing
�R
evie
w re
sults
�C
heck
val
idity
of s
olut
ion
Stre
ss A
naly
sis
-Pr
epro
cess
ing
C.
Mes
hing
�Meshing
is th
e pr
oces
s us
ed to
�fil
l� th
e so
lid m
odel
with
no
des
and
elem
ents
, i.e
, to
crea
te th
e FE
A m
odel
.�
Rem
embe
r, yo
u ne
ed n
odes
and
ele
men
ts fo
r the
fini
te e
lem
ent
solu
tion,
not
just
the
solid
mod
el.
The
solid
mod
el d
oes
NO
T pa
rtic
ipat
e in
the
finite
ele
men
t sol
utio
n.
Solid
mod
elFE
A m
odel
mes
hing
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
�Th
ere
are
thre
e st
eps
to m
eshi
ng:
�D
efin
e el
emen
t attr
ibut
es�
Spec
ify m
esh
cont
rols
�G
ener
ate
the
mes
h
�El
emen
t attr
ibut
esar
e ch
arac
teris
tics
of th
e fin
ite e
lem
ent
mod
el th
at y
ou m
ust e
stab
lish
prio
r to
mes
hing
. Th
ey
incl
ude:
�El
emen
t typ
es�
Rea
l con
stan
ts�
Mat
eria
l pro
pert
ies
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
Elem
ent T
ype
�Th
e el
emen
t typ
e is
an
impo
rtan
t cho
ice
that
det
erm
ines
the
follo
win
g el
emen
t cha
ract
eris
tics:
�D
OF
set.
A th
erm
al e
lem
ent t
ype,
for e
xam
ple,
has
one
dof:
TEM
P, w
here
as a
str
uctu
ral e
lem
ent t
ype
may
hav
e up
to s
ixdo
f: U
X, U
Y, U
Z, R
OTX
, RO
TY, R
OTZ
.�
Elem
ent s
hape
--br
ick,
tetr
ahed
ron,
qua
drila
tera
l, tr
iang
le, e
tc.
�D
imen
sion
ality
--2-
D (X
-Y p
lane
onl
y), o
r 3-D
.�
Ass
umed
dis
plac
emen
t sha
pe --
linea
r vs.
qua
drat
ic.
�A
NSY
S ha
s a
�lib
rary
� of
ove
r 150
ele
men
t typ
es fr
om w
hich
yo
u ca
n ch
oose
. D
etai
ls o
n ho
w to
cho
ose
the
�cor
rect
� el
emen
t typ
e w
ill b
e pr
esen
ted
late
r. F
or n
ow, l
et�s
see
how
to
def
ine
an e
lem
ent t
ype.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
�To
def
ine
an e
lem
ent t
ype:
�Pr
epro
cess
or >
Ele
men
t Typ
e >
Add/
Edit/
Del
ete
�[A
dd]t
o ad
d ne
w e
lem
ent
type
�C
hoos
e th
e de
sire
d ty
pe
(suc
h as
SO
LID
92) a
nd
pres
s O
K�
[Opt
ions
]to
spec
ify
addi
tiona
l ele
men
t opt
ions
�O
r use
the
ETco
mm
and:
�et
,1,s
olid
92
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
�N
otes
:�
Setti
ng p
refe
renc
es to
the
desi
red
disc
iplin
e (M
ain
Men
u >
Pref
eren
ces)
will
sho
w o
nly
the
elem
ent t
ypes
val
id fo
r tha
t di
scip
line.
�Yo
u sh
ould
def
ine
the
elem
ent t
ype
early
in th
e pr
epro
cess
ing
phas
e be
caus
e m
any
of th
e m
enu
choi
ces
in th
e G
UI a
re fi
ltere
d ou
t bas
ed o
n th
e cu
rren
t DO
F se
t. F
or e
xam
ple,
if y
ou c
hoos
e a
stru
ctur
al e
lem
ent t
ype,
ther
mal
load
cho
ices
will
be
�gra
yed
out�
or n
ot s
how
n at
all.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
Rea
l Con
stan
ts
�R
eal c
onst
ants
are
use
d fo
r geo
met
ric p
rope
rtie
s th
at c
anno
t be
com
plet
ely
defin
ed b
y th
e el
emen
t�s g
eom
etry
. Fo
r ex
ampl
e:�
A b
eam
ele
men
t is
defin
ed b
y a
line
join
ing
two
node
s. T
his
defin
es o
nly
the
leng
th o
f the
bea
m.
To s
peci
fy th
e be
am�s
cr
oss-
sect
iona
l pro
pert
ies,
suc
h as
the
area
and
mom
ent o
f in
ertia
, you
nee
d to
use
real
con
stan
ts.
�A
she
ll el
emen
t is
defin
ed b
y a
quad
rilat
eral
or t
riang
ular
are
a.
This
def
ines
onl
y th
e su
rfac
e ar
ea o
f the
she
ll. T
o sp
ecify
the
shel
l thi
ckne
ss, y
ou n
eed
to u
se re
al c
onst
ants
.�
Mos
t 3-D
sol
id e
lem
ents
do
not r
equi
re a
real
con
stan
t sin
ce th
e el
emen
t geo
met
ry is
fully
def
ined
by
its n
odes
.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
�To
def
ine
real
con
stan
ts:
�Pr
epro
cess
or >
Rea
l Con
stan
ts�
[Add
]to
add
a ne
w re
al c
onst
ant s
et.
�If
mul
tiple
ele
men
t typ
es h
ave
been
def
ined
, cho
ose
the
elem
ent t
ype
for w
hich
you
are
spe
cify
ing
real
con
stan
ts.
�Th
en e
nter
the
real
con
stan
t val
ues.
�O
r use
the
Rfa
mily
of c
omm
ands
.
�D
iffer
ent e
lem
ent t
ypes
requ
ire d
iffer
ent r
eal c
onst
ants
, and
so
me
don�
t req
uire
any
real
con
stan
ts.
Che
ck th
e El
emen
ts
Man
ual,
avai
labl
e on
-line
, for
det
ails
.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
Mat
eria
l Pro
pert
ies
�Ev
ery
anal
ysis
requ
ires
som
e m
ater
ial p
rope
rty
inpu
t:
Youn
g�s
mod
ulus
EX
for s
truc
tura
l ele
men
ts, t
herm
al
cond
uctiv
ity K
XX fo
r the
rmal
ele
men
ts, e
tc.
�Th
ere
are
two
way
s to
def
ine
mat
eria
l pro
pert
ies:
�M
ater
ial l
ibra
ry�
Indi
vidu
al p
rope
rtie
s
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
Usi
ng th
e M
ater
ial L
ibra
ry
�Th
is m
etho
d al
low
s yo
u to
cho
ose
a pr
edef
ined
set
of p
rope
rtie
s fo
r a
give
n m
ater
ial.
�A
NSY
S su
pplie
s ty
pica
l str
uctu
ral a
nd th
erm
al p
rope
rtie
s (li
near
only
) for
som
e co
mm
on m
ater
ials
, but
we
stro
ngly
reco
mm
end
that
yo
u cr
eate
you
r ow
n m
ater
ial l
ibra
ry.
�To
cho
ose
a m
ater
ial f
rom
the
libra
ry:
�Fi
rst d
efin
e th
e lib
rary
pat
h.�
Prep
roce
ssor
> M
ater
ial P
rops
>
Mat
eria
l Lib
rary
> L
ibra
ry P
ath
�En
ter t
he lo
catio
n fr
om w
hich
to
REA
D m
ater
ial d
ata,
e.g
, /a
nsys
56/m
atlib
.�
Or u
se th
e /M
PLIB
com
man
d.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng�
Then
�im
port
� a
mat
eria
l fro
m th
e lib
rary
.�
Prep
roce
ssor
> M
ater
ial L
ibra
ry >
Impo
rt Li
brar
y�
Cho
ose
the
units
sys
tem
. Th
is is
us
ed o
nly
to fi
lter t
he li
st o
f file
s sh
own
in th
e su
bseq
uent
dia
log.
A
NSY
S ha
s no
kno
wle
dge
of u
nits
an
d do
es N
OT
do u
nit c
onve
rsio
n.�
Cho
ose
the
desi
red
mat
eria
l file
, su
ch a
s st
eel A
ISI C
1020
.�
Or u
se th
e M
PREA
Dco
mm
and
with
th
e LI
B o
ptio
n.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
Spec
ifyin
g In
divi
dual
Mat
eria
l Pro
pert
ies
�In
stea
d of
cho
osin
g a
mat
eria
l nam
e, th
is m
etho
d in
volv
es
dire
ctly
spe
cify
ing
the
requ
ired
prop
ertie
s.
�To
spe
cify
indi
vidu
al p
rope
rtie
s:�
Prep
roce
ssor
> M
ater
ial P
rops
>
Isot
ropi
c�
Spec
ify m
ater
ial n
umbe
r, us
ually
1.
�Th
en e
nter
the
indi
vidu
al
prop
erty
val
ues.
�O
r use
the
MP
com
man
d.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
A N
ote
on U
nits
�Yo
u do
not
nee
d to
tell
AN
SYS
the
syst
em o
f uni
ts y
ou a
re
usin
g. S
impl
y de
cide
wha
t uni
ts y
ou w
ill u
se, t
hen
mak
e su
re
all o
f you
r inp
ut is
con
sist
ent.
�Fo
r exa
mpl
e, if
the
mod
el g
eom
etry
is in
inch
es, m
ake
sure
that
al
l oth
er in
put d
ata
�m
ater
ial p
rope
rtie
s, re
al c
onst
ants
, loa
ds,
etc.
�ar
e in
term
s of
inch
es.
�A
NSY
S do
es N
OT
do u
nits
con
vers
ion!
It s
impl
y ac
cept
s al
l nu
mbe
rs y
ou in
put w
ithou
t que
stio
ning
thei
r val
idity
.
�Th
e co
mm
and
/UN
ITS
allo
ws
you
to s
peci
fy a
uni
ts s
yste
m,
but i
t is
sim
ply
a re
cord
ing
devi
ce to
let o
ther
use
rs o
f you
r m
odel
kno
w w
hat u
nits
you
use
d.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
Spec
ifyin
g M
esh
Con
trol
sis
the
seco
nd s
tep
in m
eshi
ng.
�M
any
mes
h co
ntro
ls a
re a
vaila
ble
in A
NSY
S. F
or n
ow, w
e w
ill
pres
ent a
sim
ple
met
hod
of s
peci
fyin
g m
esh
dens
ity, c
alle
dSm
artS
izin
g.
�Sm
artS
izin
gis
an
algo
rithm
that
ass
igns
ele
men
t div
isio
ns to
al
l lin
es in
the
mod
el b
ased
on
line
leng
th, c
urva
ture
, and
pr
oxim
ity to
hol
es, e
tc.
�Yo
u si
mpl
y sp
ecify
a �
size
leve
l� ra
ngin
g fr
om 1
(ver
y fin
e m
esh)
to 1
0 (v
ery
coar
se m
esh)
, and
AN
SYS
take
s ca
re o
f the
re
st.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
�Th
eM
eshT
ooli
s th
e be
st w
ay to
spe
cify
mes
h co
ntro
ls:
�Pr
epro
cess
or >
Mes
hToo
l.�
Act
ivat
eSm
artS
izin
g. S
ize
leve
l def
aults
to 6
.
Gen
erat
ing
the
mes
his
the
final
ste
p in
mes
hing
.
�Fi
rst s
ave
the
data
base
.
�Th
en p
ress
[Mes
h]in
the
Mes
hToo
l.�
This
brin
gs u
p a
pick
er.
Pres
s [P
ick
All]
in th
e pi
cker
to
indi
cate
all
entit
ies.
Stre
ss A
naly
sis
-Pr
epro
cess
ing
...M
eshi
ng
�W
hen
the
mes
hing
is c
ompl
ete,
AN
SYS
will
aut
omat
ical
ly p
lot
the
elem
ents
.�
The
defa
ult e
lem
ent p
lot s
how
s al
l ele
men
t edg
es a
s st
raig
ht
lines
eve
n fo
r a q
uadr
atic
ele
men
t typ
e.�
To s
how
cur
ved
elem
ent e
dges
, iss
ue /E
FAC
ET,2
(or U
tility
Men
u >
Plot
Ctrl
s>
Size
and
Sha
pe�
).
Stre
ss A
naly
sis
-Pr
epro
cess
ing
�M
eshi
ng
�Pr
epro
cess
ing
!G
eom
etry
!M
eshi
ng
�So
lutio
n�
Load
ing
�So
lve
�Po
stpr
oces
sing
�R
evie
w re
sults
�C
heck
val
idity
of s
olut
ion
Stre
ss A
naly
sis
-So
lutio
nD
. Lo
adin
g
�Th
e so
lutio
n st
ep is
whe
re w
e ap
ply
load
s on
the
obje
ct a
nd
let t
he s
olve
r cal
cula
te th
e fin
ite e
lem
ent s
olut
ion.
�Lo
ads
are
avai
labl
e bo
th in
the
Solu
tion
and
Prep
roce
ssor
m
enus
.
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
�Th
ere
are
five
cate
gorie
s of
load
s:D
OF
Con
stra
ints
Spec
ified
DO
F va
lues
, suc
h as
di
spla
cem
ents
in a
str
ess
anal
ysis
or
tem
pera
ture
s in
a th
erm
al a
naly
sis.
Con
cent
rate
d Lo
ads
Poin
t loa
ds, s
uch
as fo
rces
or h
eat f
low
ra
tes.
Surf
ace
Load
sLo
ads
dist
ribut
ed o
ver a
sur
face
, suc
h as
pr
essu
res
or c
onve
ctio
ns.
Bod
y Lo
ads
Volu
met
ric o
r fie
ld lo
ads,
suc
h as
te
mpe
ratu
res
(cau
sing
ther
mal
exp
ansi
on)
or in
tern
al h
eat g
ener
atio
n.In
ertia
Loa
dsLo
ads
due
to s
truc
tura
l mas
s or
iner
tia,
such
as
grav
ity a
nd ro
tatio
nal v
eloc
ity.
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
�Yo
u ca
n ap
ply
load
s ei
ther
on
the
solid
mod
el o
r dire
ctly
on
the
FEA
mod
el (n
odes
and
ele
men
ts).
�So
lid m
odel
load
s ar
e ea
sier
to a
pply
bec
ause
ther
e ar
e fe
wer
en
titie
s to
pic
k.�
Mor
eove
r, so
lid m
odel
load
s ar
e in
depe
nden
t of t
he m
esh.
You
do
n�t n
eed
to re
appl
y th
e lo
ads
if yo
u ch
ange
the
mes
h.
Con
stra
int
on li
ne
Solid
mod
el
Pres
sure
on
line
Forc
e at
key
poin
t
Con
stra
ints
at
nod
es
FEA
mod
el
Pres
sure
s on
ele
men
t fac
es
Forc
e at
nod
e
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
�R
egar
dles
s of
how
you
app
ly th
e lo
ads,
the
solv
er e
xpec
ts a
ll lo
ads
to b
e in
term
s of
the
finite
ele
men
t mod
el.
Ther
efor
e,
solid
mod
el lo
ads
are
auto
mat
ical
ly tr
ansf
erre
dto
the
unde
rlyin
g no
des
and
elem
ents
dur
ing
solu
tion.
�W
e w
ill n
ow d
iscu
ss h
ow to
app
ly th
e fo
llow
ing
type
s of
st
ruct
ural
load
s:�
Dis
plac
emen
t con
stra
ints
�Pr
essu
res
�G
ravi
ty
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
Dis
plac
emen
t Con
stra
ints
�U
sed
to s
peci
fy w
here
the
mod
el is
fixe
d (z
ero
disp
lace
men
t lo
catio
ns).
�C
an a
lso
be n
on-z
ero,
to s
imul
ate
a kn
own
defle
ctio
n.
�To
app
ly d
ispl
acem
ent c
onst
rain
ts :
�So
lutio
n >
-Loa
ds-A
pply
> D
ispl
acem
ent
�C
hoos
e w
here
you
wan
t to
appl
y th
e co
nstr
aint
.�
Pick
the
desi
red
entit
ies
in th
e gr
aphi
cs w
indo
w.
�Th
en c
hoos
e th
e co
nstr
aint
di
rect
ion.
Val
ue d
efau
lts to
zer
o.�
Or u
se th
e D
fam
ily o
f com
man
ds:
DK,
DL,
DA,
D.
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
�D
ispl
acem
ent c
onst
rain
ts a
re a
lso
used
to e
nfor
ce s
ymm
etry
oran
tisym
met
rybo
unda
ry c
ondi
tions
.�
Sym
met
ry B
C:
Out
-of-p
lane
dis
plac
emen
ts a
nd in
-pla
ne
rota
tions
are
fixe
d.�
Ant
isym
met
ryB
C:
In-p
lane
dis
plac
emen
ts a
nd o
ut-o
f-pla
ne
rota
tions
are
fixe
d.
Sym
met
ry B
ound
ary
UX=
0R
OTY
=RO
TZ=0
Antis
ymm
etry
Boun
dary
UY=
UZ=
0R
OTX
=0
Y
X
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
Pres
sure
s
�To
app
ly a
pre
ssur
e:�
Solu
tion
> -L
oads
-App
ly >
Pre
ssur
e�
Cho
ose
whe
re y
ou w
ant t
o ap
ply
the
pres
sure
--us
ually
on
lines
for 2
-D
mod
els,
on
area
s fo
r 3-D
mod
els.
�Pi
ck th
e de
sire
d en
titie
s in
the
grap
hics
win
dow
.�
Then
ent
er th
e pr
essu
re v
alue
. A
po
sitiv
e va
lue
indi
cate
s a
com
pres
sive
pre
ssur
e (a
ctin
g to
war
ds th
ece
ntro
idof
the
elem
ent).
�O
r use
the
SFfa
mily
of c
omm
ands
: SF
L, S
FA, S
FE, S
F.
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
�Fo
r a 2
-D m
odel
, whe
re
pres
sure
s ar
e us
ually
app
lied
on a
line
, you
can
spe
cify
a
tape
red
pres
sure
by
ente
ring
a va
lue
for b
oth
the
I and
J e
nds
of th
e lin
e.
�I a
nd J
are
det
erm
ined
by
the
line
dire
ctio
n. I
f you
see
the
tape
r goi
ng in
the
wro
ng
dire
ctio
n, s
impl
y re
appl
y th
e pr
essu
re w
ith th
e va
lues
re
vers
ed.
VALI
= 5
00
VALI
= 5
00VA
LJ =
100
0
VALI
= 1
000
VALJ
= 5
00
500
L350
0
L3
1000
500
L3
1000
500
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
Gra
vity
�To
app
ly g
ravi
tatio
nal a
ccel
erat
ion:
�So
lutio
n >
-Loa
ds-A
pply
> G
ravi
ty�
Or u
se th
e AC
ELco
mm
and.
�N
otes
:�
A p
ositi
veac
cele
ratio
n va
lue
caus
es d
efle
ctio
n in
the
nega
tive
dire
ctio
n. I
f Y is
poi
ntin
g up
war
ds, f
or e
xam
ple,
a p
ositi
ve
AC
ELY
valu
e w
ill c
ause
the
stru
ctur
e to
mov
e do
wnw
ards
.�
Den
sity
(or m
ass
in s
ome
form
) mus
t be
defin
ed fo
r gra
vity
and
ot
her i
nert
ia lo
ads.
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
Verif
ying
app
lied
load
s
�Pl
ot th
em b
y ac
tivat
ing
load
sym
bols
:�
Util
ity M
enu
>Pl
otC
trls
> Sy
mbo
ls�
Com
man
ds --
/PBC
, /PS
F, /P
BF
�O
r lis
t the
m:
�U
tility
Men
u >
List
> L
oads
>
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
Mod
ifyin
g an
d D
elet
ing
Load
s
�To
mod
ify a
load
val
ue, s
impl
y re
appl
y th
e lo
ad
with
the
new
val
ue.
�To
del
ete
load
s:�
Solu
tion
> -L
oads
-Del
ete
>�
Whe
n yo
u de
lete
sol
id m
odel
load
s, A
NSY
S al
so
auto
mat
ical
ly d
elet
es a
ll co
rres
pond
ing
finite
el
emen
t loa
ds.
Stre
ss A
naly
sis
-So
lutio
n...
Load
ing
�Pr
epro
cess
ing
!G
eom
etry
!M
eshi
ng
�So
lutio
n!
Load
ing
�So
lve
�Po
stpr
oces
sing
�R
evie
w re
sults
�C
heck
val
idity
of s
olut
ion
Stre
ss A
naly
sis
-So
lutio
nE.
Sol
ve
�Th
e so
lve
step
is w
here
you
let t
he s
olve
r cal
cula
te th
e fin
ite
elem
ent s
olut
ion.
�Fi
rst,
it is
a g
ood
idea
to re
view
and
che
ck y
our a
naly
sis
data
,e.
g: �C
onsi
sten
t uni
ts�
Elem
ent t
ypes
, opt
ions
, and
real
con
stan
ts�
Mat
eria
l pro
pert
ies
�D
ensi
ty if
iner
tia lo
adin
g�
Coe
ffici
ent o
f the
rmal
exp
ansi
on if
ther
mal
str
ess
�M
esh
dens
ity, e
spec
ially
in s
tres
s co
ncen
trat
ion
regi
ons
�Lo
ad v
alue
s an
d di
rect
ions
�R
efer
ence
tem
pera
ture
for t
herm
al e
xpan
sion
s
Stre
ss A
naly
sis
-So
lutio
n�
Solv
e
�To
initi
ate
the
solv
e:�
Firs
t sav
e th
e da
taba
se!
�Th
en:
�So
lutio
n >
-Sol
ve-C
urre
nt L
S�
Or i
ssue
the
SOLV
Eco
mm
and.
�Th
e so
lver
writ
es re
sults
dat
a to
the
in-m
emor
y da
taba
se a
ndto
the
resu
lts fi
le,j
obna
me.
rst(
or
.rth,
.rm
g, .r
fl).
Res
ults
Res
ults
Dat
a
Dat
abas
e
Inpu
tD
ata
Res
ults
File
Solv
er
Stre
ss A
naly
sis
-So
lutio
n�
Solv
e
�D
urin
g so
lutio
n, A
NSY
S pr
ovid
es a
lot o
f use
ful i
nfor
mat
ion
in th
e O
utpu
t Win
dow
, suc
h as
:�
Mas
s pr
oper
ties
of th
e m
odel
�Th
e m
ass
calc
ulat
ion
is q
uite
acc
urat
e;ce
ntro
idan
d m
ass
mom
ent
calc
ulat
ions
are
roug
h ap
prox
imat
ions
�R
ange
of e
lem
ent m
atrix
coe
ffici
ents
�M
ay in
dica
te a
pro
blem
with
mat
eria
l pro
pert
ies
or re
al c
onst
ants
if
max
imum
/min
imum
ratio
> 1
.0E8
�M
odel
siz
e an
d so
lver
sta
tistic
s�
Sum
mar
y of
file
s w
ritte
n an
d th
eir s
izes
:�
jobn
ame.
emat
-ele
men
t mat
rix fi
le�
jobn
ame.
esav
-ele
men
t sav
ed d
ata
file
�jo
bnam
e.tri
-tria
ngul
ariz
edm
atrix
file
�jo
bnam
e.rs
t-re
sults
file
Stre
ss A
naly
sis
-So
lutio
n�
Solv
e
�Pr
epro
cess
ing
!G
eom
etry
!M
eshi
ng
�So
lutio
n!
Load
ing
!So
lve
�Po
stpr
oces
sing
�R
evie
w re
sults
�C
heck
val
idity
of s
olut
ion
Stre
ss A
naly
sis
-Po
stpr
oces
sing
F. R
evie
win
g R
esul
ts
�Po
stpr
oces
sing
is w
ithou
t dou
bt th
e m
ost i
mpo
rtan
t ste
p in
an
ana
lysi
s. Y
ou m
ay b
e re
quire
d to
mak
e de
sign
dec
isio
ns
base
d on
the
resu
lts, s
o it
is a
goo
d id
ea n
ot o
nly
to re
view
th
e re
sults
car
eful
ly, b
ut a
lso
to c
heck
the
valid
ity o
f the
so
lutio
n.
�A
NSY
S ha
s tw
o po
stpr
oces
sors
:�
POST
1, th
e G
ener
al P
ostp
roce
ssor
, to
revi
ew a
sin
gle
set o
f re
sults
ove
r the
ent
ire m
odel
.�
POST
26, t
he T
ime-
His
tory
Pos
tpro
cess
or, t
o re
view
resu
lts a
t se
lect
ed p
oint
s in
the
mod
el o
ver t
ime.
Mai
nly
used
for t
rans
ient
an
d no
nlin
ear a
naly
ses.
(N
ot d
iscu
ssed
in th
is c
ours
e.)
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...R
evie
win
g R
esul
ts
�R
evie
win
g re
sults
of a
str
ess
anal
ysis
gen
eral
ly in
volv
es:
�D
efor
med
sha
pe�
Stre
sses
�R
eact
ion
forc
es
Def
orm
ed S
hape
�G
ives
a q
uick
indi
catio
n of
whe
ther
the
load
s w
ere
appl
ied
in
the
corr
ect d
irect
ion.
�Le
gend
col
umn
show
s th
e m
axim
um d
ispl
acem
ent,
DM
X.
�Yo
u ca
n al
so a
nim
ate
the
defo
rmat
ion.
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...R
evie
win
g R
esul
ts
�To
plo
t the
def
orm
ed
shap
e:�
Gen
eral
Post
proc
> Pl
ot
Res
ults
> D
efor
med
Sha
pe�
Or u
se th
e PL
DIS
Pco
mm
and.
�Fo
r ani
mat
ion:
�U
tility
Men
u >
Plot
Ctrl
s>
Anim
ate
> D
efor
med
Sha
pe�
Or u
se th
e AN
DIS
Pco
mm
and.
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...R
evie
win
g R
esul
ts
Stre
sses
�Th
e fo
llow
ing
stre
sses
are
typi
cally
ava
ilabl
e fo
r a 3
-D s
olid
m
odel
:�
Com
pone
nt s
tres
ses
�SX
, SY,
SZ,
SXY
, SYZ
, SXZ
(glo
bal
Car
tesi
an d
irect
ions
by
defa
ult)
�Pr
inci
pal s
tres
ses
�S1
, S2,
S3,
SEQ
V(v
onM
ises
), SI
NT
(str
ess
inte
nsity
)
�B
est v
iew
ed a
s co
ntou
r plo
ts, w
hich
allo
w y
ou to
qui
ckly
lo
cate
�ho
t spo
ts�
or tr
oubl
e re
gion
s.�
Nod
al s
olut
ion:
Stre
sses
are
ave
rage
d at
the
node
s, s
how
ing
smoo
th, c
ontin
uous
con
tour
s.�
Elem
ent s
olut
ion:
No
aver
agin
g, re
sulti
ng in
dis
cont
inuo
us
cont
ours
.
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...R
evie
win
g R
esul
ts
�To
plo
t str
ess
cont
ours
:�
Gen
eral
Post
proc
> Pl
ot R
esul
ts >
Nod
alSo
lu�
or P
LNSO
Lco
mm
and
�G
ener
alPo
stpr
oc>
Plot
Res
ults
> E
lem
entS
olu�
or P
LESO
Lco
mm
and
�Yo
u ca
n al
so a
nim
ate
stre
ss c
onto
urs:
�U
tility
Men
u >
Plot
Ctrl
s>
Anim
ate
> D
efor
med
Res
ults
... o
r AN
CN
TRco
mm
and
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...R
evie
win
g R
esul
ts
A N
ote
onPo
wer
Gra
phic
s
�It
is th
e de
faul
t gra
phic
s se
tting
(/G
RAP
H,P
OW
ER).
�Pl
ots
only
the
visi
ble
surf
aces
and
igno
res
ever
ythi
ng �
unde
rnea
th.�
�A
dvan
tage
s:�
Fast
erre
plot
, cris
p gr
aphi
cs.
�Sm
ooth
, alm
ost p
hoto
-rea
listic
dis
play
s.�
Prev
ents
str
ess
aver
agin
g ac
ross
mat
eria
l and
real
co
nsta
nt b
ound
arie
s.
�To
dea
ctiv
ate
Pow
erG
raph
ics
(or a
ctiv
ate
�ful
l gr
aphi
cs�)
:�
Tool
bar >
PO
WER
GR
PH�
Or i
ssue
/GR
APH
,FU
LL.
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...R
evie
win
g R
esul
ts
Rea
ctio
n Fo
rces
�Th
e su
m o
f the
reac
tion
forc
es in
eac
h di
rect
ion
mus
t equ
al
the
sum
of a
pplie
d lo
ads
in th
at d
irect
ion.
�B
est v
iew
ed a
s a
listin
g:�
Gen
eral
Pos
tpro
cess
or >
Lis
t Res
ults
> R
eact
ion
Solu
tion�
or
PRR
SOL
com
man
d
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...R
evie
win
g R
esul
ts
�Pr
epro
cess
ing
!G
eom
etry
!M
eshi
ng
�So
lutio
n!
Load
ing
!So
lve
�Po
stpr
oces
sing
!R
evie
w re
sults
�C
heck
val
idity
of s
olut
ion
Stre
ss A
naly
sis
-Po
stpr
oces
sing
G.
Che
ckin
g Va
lidity
of S
olut
ion
�It
is a
lway
s a
good
idea
to d
o a
�san
ity c
heck
� an
d m
ake
sure
th
at th
e so
lutio
n is
acc
epta
ble.
�W
hat y
ou n
eed
to c
heck
dep
ends
on
the
type
of p
robl
em y
ou
are
solv
ing,
but
her
e ar
e so
me
typi
cal q
uest
ions
to a
sk:
�D
o th
e re
actio
n fo
rces
bal
ance
the
appl
ied
load
s?
�W
here
is th
e m
axim
um s
tres
s lo
cate
d?�
If it
is a
t a s
ingu
larit
y, s
uch
as a
poi
nt lo
ad o
r a re
-ent
rant
cor
ner,
the
valu
e is
gen
eral
ly m
eani
ngle
ss.
(We
will
dis
cuss
mor
e ab
out
this
in C
hapt
er 5
.)
�A
re th
e st
ress
val
ues
beyo
nd th
e el
astic
lim
it?�
If so
, the
load
mag
nitu
des
may
be
wro
ng, o
r you
may
nee
d to
do
a no
nlin
ear a
naly
sis.
Stre
ss A
naly
sis
-Po
stpr
oces
sing
...C
heck
ing
Valid
ity o
f Sol
utio
n
�Is
the
mes
h ad
equa
te?
�Th
is is
alw
ays
deba
tabl
e, b
ut y
ou c
an g
ain
conf
iden
ce in
the
mes
h by
usi
ng e
rror
est
imat
ion
data
(dis
cuss
ed in
Cha
pter
14)
.�
Oth
er w
ays
to c
heck
mes
h ad
equa
cy:
�Pl
ot th
e el
emen
t sol
utio
n (u
nave
rage
dst
ress
es) a
nd lo
ok fo
r el
emen
ts w
ith h
igh
stre
ss g
radi
ents
. Th
ese
regi
ons
are
cand
idat
es fo
r mes
h re
finem
ent.
�If
ther
e is
a s
igni
fican
t diff
eren
ce b
etw
een
the
noda
l (a
vera
ged)
and
ele
men
t (un
aver
aged
) str
ess
cont
ours
, the
m
esh
may
be
too
coar
se.
�Si
mila
rly, i
f the
re is
a s
igni
fican
t diff
eren
ce b
etw
een
Pow
erG
raph
ics
and
full
grap
hics
str
esse
s, th
e m
esh
may
be
too
coar
se.
�R
e-m
esh
with
twic
e as
man
y el
emen
ts, r
e-so
lve,
and
com
pare
th
e re
sults
. (B
ut th
is m
ay n
ot a
lway
s be
pra
ctic
al.)
Stre
ss A
naly
sis
�Pr
epro
cess
ing
!G
eom
etry
!M
eshi
ng
�So
lutio
n!
Load
ing
!So
lve
�Po
stpr
oces
sing
!R
evie
w re
sults
!C
heck
val
idity
of s
olut
ion
Stre
ss A
naly
sis
H.
Wor
ksho
p
�Th
is w
orks
hop
cons
ists
of t
wo
prob
lem
s:2A
. La
the
Cut
ter
2B.
2-D
Cor
ner B
rack
et T
utor
ial
Ref
er to
you
r Wor
ksho
p Su
pple
men
tfor
inst
ruct
ions
.
