plastic hinge- warwick
DESCRIPTION
plastic hingesTRANSCRIPT
-
Resis
tance o
f ste
el beam
s (
ela
stic)
Th
ere
are
two
sit
uati
on
sto
co
nsid
er.
1.
Ela
sti
cfa
ilu
rew
ill
occu
rw
hen x.m
ax
=x.m
ax
yo
rf y
.
I
Melis
the
mo
men
tat
on
set
of
yie
ldin
g(i
.e.y
ymax
xx
xx
fW
fyI
MM
Mel
el
max
.max
!!
!!
Gx
Melis
the
mo
men
tat
on
set
of
yie
ldin
g(i
.e.
the
ela
sti
clim
it).
Fo
ra
recta
ng
ula
rsecti
on
of
dep
thh
an
dw
idthb
sh
ow
the
ela
sti
csecti
on
mo
du
lusW
elisbh
2/6
.O
nP
g.4
8o
fD
ata
Bo
okW
eliszxx
(secti
on
mo
du
lus)
Fo
rm
om
en
t>M
el
the
gen
era
lexp
ressio
nfo
rela
sti
cb
en
din
gis
no
lon
ger
valid
.
18
-
Resis
tance o
f ste
el beam
s (
pla
stic)
2.M
max
fro
m1
isN
OT
the
hig
he
stM
that
the
ste
elb
ea
mc
an
res
ist.
Th
isis
fW
MM
M!
!!
f y
Mxx
max
Mp
lis
the
mo
men
tw
hen
the
full
secti
on
has
yie
lded
(i.e
.it
isfu
lly
pla
sti
c).
yxx
fW
MM
Mp
lp
lm
ax
.max
!!
!Mxx.m
ax
y(
yp
)
Fo
ra
recta
ng
ula
rsecti
on
of
dep
thh
an
dw
idth
b,
the
pla
sti
csecti
on
mo
du
lusW
plisbh
2/4
(i.e
.f y
f yf y
ff
Wp
l=
1.5W
el)
"Yf
y
f yf y
f yf y
""Y
"Y
fy
f yf y
f y
Develo
pm
en
to
fy
ield
ing
thro
ug
hd
ep
tho
fsecti
on
y
Ide
aliz
ed
str
ess-s
tra
in c
urv
e
for
mild
ste
el
19
Develo
pm
en
to
fyie
ldin
gth
rou
gh
dep
tho
fsecti
on
asM
is in
cre
ased
.
-
Pla
stic
mom
ent
Pla
stic
mom
ent
Pure
bendin
gso
no
axia
llo
ad,
the
sum
of
fy
#!
Af
AfP
ure
bendin
gso
no
axia
llo
ad,
the
su
mof
no
rma
l fo
rce
on
th
e s
ectio
n is s
till
0:
AA
A!
!
fy
#!
21
Af
Af
yy
22
1A
A!
!
Th
epla
stic
ne
utr
alaxis
div
ide
sth
eT
he
pla
stic
neutr
ala
xis
div
ides
the
beam
section into
tw
o p
art
s o
f equal
are
as.
fy
)(
22
1y
yA
fM
yPI
$!
Pla
stic a
na
lysis
is u
se
d to
de
term
ine
loa
ds t
ha
t p
rod
uce
co
llap
se
.
20
-
Pla
stic
hin
ges
Pla
stic
hin
ges
WW
MPI
MPI
Incre
ase
Wu
ntill
the
mo
me
nta
tm
id-
MPI
Incre
ase
Wu
ntill
the
mo
me
nta
tm
id
sp
an
re
ach
es th
e p
lastic m
om
en
t.
Un
restr
icte
d p
lastic flo
w a
t th
is s
ectio
n
occu
rs. L
arg
e d
efo
rma
tio
n ta
ke
s p
lace
with
no
incre
ase
inlo
ad
with
no
incre
ase
inlo
ad
.
In th
is c
ase
th
e b
ea
m w
as o
rig
ina
lly
sta
tica
lly in
de
term
ina
te, co
llap
se
will
Pla
stic
hin
ge
Sin
ce
the
be
am
wa
so
rig
ina
llysta
tica
lly
ha
pp
en
aft
er
2 p
lastic h
ing
es a
re
form
ed
.
Nt
l
hi
it
21
Sin
ce
the
be
am
wa
so
rig
ina
llysta
tica
lly
de
term
ina
te, th
e p
rese
nce
of a
pla
stic
hin
ge
le
ad
s to
co
llap
se
.
No
te: a
re
al
hin
ge
ca
rrie
s n
o m
om
en
t,
wh
ile th
e p
lastic h
ing
e s
till
ca
rrie
s M
PI.