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.,. C'.......L- 1. ~...,
T..
-' 0: ....
....:'..r. r.r: S.
Ii •
eele
1
.,
T e ~eport gives a sumrr.a~ized p_e entation of +ne four
theories deve~oped for t e c . utaticl of t"e deflect~ons or
beams. the application of the heories to va~ious beam and
connection tes s is disc ssed, an the theo~et1cal resu~ts
a 4 e co~pared witn the test results~ l~O+ all studies are COl
plete because of the limite ti e available in ~. ~. 113.,
and it wil oe necess ry to do some f rther worK on the co
putatio: of theoretics: curves •
•
.-
,"'....1 u:-~ <...
....,:: c .. e
u .... l_ A...Y
.... _0 ,y
•
• • •
• •
•
...1
2
..
.......:......
r.. e e 0..; nJ.J" Ie ~al
L i~ures and
f' e5! S, continuou~ beams
L
UOU 1'r.
T e ptlrp)se
.. ir COFPO:lt:l:ts·'.
t, is re rt ~s to s l:')8.d defle,:t ion
relations 1p tween the t~st result a d the ~heorles t~8t ...have been developed by va~ious researcners :n this field.
Sc::)pe
This stul1y was conducted on the basis of a three crea.it
hour course. ~he tiree as li ited, tlerefore, and so~ sub-
e~!s could o~ly be touched po~ because o~ the lack of time.
In the cont L uous De m se es pract ically a ... l vea I.S ..'ere in
veEtig8ted ara. the res~lts plottea. uP. rom the connections,/'
ts. everal nJ~ arisons were
only "fe ~ere sleeted or s
uf the simply s ported bea~
dy an~ presenI . ~~,
in t his report.
made and discussed in the repo t.
.t .....l..- .I. 1u... oJ
.- vU Lloi t ~a 0:
"_!'e~~ r "il :ar.l .; lJ••-~
..... L:m: ;:, . ' '"4 ......~- .l._
::I"TJ
" . j uer
-2-
To_ first sec:ion of the report ~ e~ent t.e r ur de-
flec~ion theo~i~s and the ad .t ges ar: disad ontaGes of
each t.lec:-y. "=>everal fi res are i elude' we i h explain
certa'n aspects )f each theo~y.
I!i he second part of the report. tr. e ,9.. icati.ll of the
1 rt omin s of t.e theories
S disCll"
I is very v: ~nt,'" ... rf r~nt testv5r~o s theories to
frol a 1 10+ ... :Lat:n t:.e hi uer :'ast'c tln'e I.d .?ar 10-
. larl i.r .... e s .. i'l- ar
at :: is 01 t i very .i h f. Le
e e ::'e_+ f tIeJJ. ....
• I.. .;: _= U6.:. hortc _:.. .... n •
.-... : t . eul . )
c . p the . r... 0 fshe'i. tt1
fo
. nd i~..; sed •
wubjec , to B:, to find
teel remuer-.
-...-
e 11 it +ions o~ d~fle~.1 ns f ~
J'he oe .... 1\" e uati . for fincins 1-: e deflectL.. n... = - - \r'i .. i!.J~icates) o~ ~o ..:..·~e, the
is,
_ rota-
tio. of tV! f.L r.e .• lent;..t: apa ... t. ....n t .. e el t:.c
" ge, t h i =e1 t 1..
¢ : ~l. It .as oe fo~
~m 11 stic ef... ectio .. r ~ "I.l. • tha tb rela.' r~s .. ·p 1s
':
n longer linear.
'or detern inate struc ures, he ..,eflec!.<: 0... c . ue fo lnd
e~s 'I.' be.... ause t' .." mo ~. t i_ 1. de.. c dent of" tn,:; -e.lectlon
aLd t e X~¢ curve can e in e rated by numerical or nalyt1cal
me~hods.
III statically inoeter ir.a te s true 'ures, howt;'ver, this is
n ~ possible and a new idea has to be introduced t et re-::;ults. 'his is done y considering tne cont n ity at t e
boundaries. n the following, four .e~hods are discussed
ri;3fly by 'uich deflections cati be s .... lvcu.
~imple Plastic ~heor
~fue ... a otruc ure is loadwd be.ond the elastic imit it
goes int w e plastic ra get ~he stru ture ~ill car'Y load
'nti 't laS Oecor....e C lurle el plastic•.~w ~ •• ·s taint, a
.. U
-4-
hinge is deve'oped at the support and continued loading
, ill produce more deflect1 .• T 1 Ii o::aent at this point is•
called the plastic hinge 0 ent. '1 he 18[,raI_s will explain
this:
Zlast1c Ir.i tiel1 ... tic
Plas . cF nr-e
N.A
c.
'i'his tht::ory ~ mp· e ly net.;:ec~s whe straL -hardening
.. effe~~ 8Ld ¥'ll, tlerefore i Te 0.1.:" approx'mate res It •
H wever, since eflectio. ~S usually li~1te by spe~ificat10~s,
the strai h r eni:l c' effect ill be of· little influence on
t ,Le result and fa ir a ..$wers can oe expec ted in t !'J.e early part
I t e pIa-tic range.
,e iskopf' s Letbod
l'his ap oach is also called the rr.ethod of mathelhatical
in egration. It h s different e ua ons for t.e thr6e parts
of the '.:- cirve elastic, nlastic, st ....aln-!1 den1 • l~'h
c'lo' i. ai I arr..'7il_ s ow t ese . ,",le t ions:
..
-~- ---------------------
-~-
A'- - -, --.;------=-=--=-=-=-::::--:-=--=-=--=----=~---B.-
Mo i----r
Mp
M
o ¢
Loment-~ atlon I,,; rve
iel pint of tile aterial
: ~I for >1 stic portio
6'.' V Crt: ~ ~.~ fo ... plastic portion..
-'
.. (f,
ondi equat ons are:F
l:p = plastic linge mo nt
¢d2 M- !..Zdx.... • -:BT""
A a d l:S are consta 1ts of the material i- t e trein har en1ng
!
range •
. he cor:putation car.. e s 'mplified ne lecti~ t:e
.rain harden"Ii;, froll.rl or to IJ. 'h s
an e
ne elastic
el1min tea a d lef¢ i
las~ 1c range in t ".e t .rl;:~ ,leis opf equ t ion •
f=o~ 0 to al.an" the pl~..... 0 ge " i 1 t ..e exte d...
f~om1 to an +~o
A -, ....... \wt
~he second eq tion 0
¢2"
•v-...
-c-
2¢ & 1.3
In symet4ic - " loaded struct .... es, e_e e 1 a lor.s c n..."
..e int ~a",e ve y sir. n::'y ..0 11 \ ark sn rter.
,.l he 8S-•
v tion aoe t ~ -ia t ~ fa .... fr eisl f' ... o_y and
e'1vE:o ace ra:e ~es It • ... or t: i tethod the tier ectiOI c
will e of the sar, e s 8. e, as ",U?VB .. J'"Len~ncies b~"': eel th's t etho c:h 0 ~ ••e or! ' ...1&- i",1 kc f
n..eth d, bL.t ••ley do not a ..o r.: tu ~ :ilffel'e (.~ foe than
InOl 1.t •
Fe.......... ter: t "' ~..1 L. d easi b~' • ! er.s io•. s 0 t e ...-'/; i . ~m.
.. 5 ~eq 1-e5, of ~_u~s~, .. 0 t t e 'tre s-~t ain I lation of
1. inceterl 1.. ate ::.tr c-, ,o
.. res olu t ions a. be~ 0:' a serie;:;. of r lfJ.xat· o__~...
"he str .. u e is e::"st'c aLj t.e aef e : on c
u e b~~o='in~ to t~e e1 oJ C theori~s. 1f, 1. wev r, t 11
.Lor:.el.t ets ::'arge- ;;:an thE; yie::'d .orr.~I.t, tae shear at t:.e
t.e struot' .....e, :r .:. t ':'s c 1 tiL \1<:, 1',11 not e
aro; a Q :.e ax~s as to 1.1 e .. , r:':'s ie ne :r..ro t.: ..
t ... tion i tn Dear is z
'..ls D.e .0 ~ ~ duces t. e ost acc": e" re5 '1- • it Co so r",-
ui as rea t 81'.0 t If i e:;:-ef - ,no ale •. 9 OIly ryl ce wn.~~ : .~S ~e 4- .... r:ot... 1 the e r: st 1"" .... 8 .. .e..:aus~
1 '" r S5"" . ne ._...oe" 8.
o .. ,.e
...
Or ly the ear y plasti0 ra.nge ".,as c ~p te f r these
bea:r.s nec' se not enough ti e was aVliilucle to fig re th
t£leoretical curves for the whole ran r;e. .l;i.S far as toe
theoretical curves were con.,uted, ho.,./ev:> r t ley snO'l1 GX-
cellent a 'reerrent uetween test result. 8Ld theory Lhe~ ,
iscre,a c' for the as de~ivereu wears y8s less tlar. t.at for~ ~
t e ~nnealeQ onev. ~ pare.tly t ,e ar eb'in ~oes not in-,
crease toe stren ~th of t!ie M~' ers a: preciaul '.
.-nly test ... o. 3 s' .O,ie ..... a lllore than 1 IV • ifference be-
t~een theor and test. Po epnarent an_ er can De give
tho gh for this, because all toe test ~un iti ns ~ere ex-
aetly the s me
!..os t of tie studies 'fer made o. the c ntinuous eanlS
.shd co.. pl~te ~urves were plotted for almo t all C3U!lS. .in
the COT... t inuous t:::a " series, lar~e - se t;;T) • ...; 1_ .. l"eCl:ime ap arent
and "') i:1t 0Ut t.1_ sh rteo 11 g" of the tieo les.•
In al_ ses, tr.e .;J eld int tL 1 test is -0-&
pro:.i..ate y 1 elO'1 t: ~ "•.eore 1: ice.l ~o P' te . v lue. ',1e] -e ',od lY g) n-9.S tee bi€..l1est y e a • + "Ih eh is-~ .0_I:
iu. uti ir. ...et-:. i . t,e - n ry. .1.1 s
, :i t a •.
ex t,U] .... o' = •10_ 0:3 • J
.p~
~ 7 .ic !.~ ." r..,.-t,e r.- •• .J .. ~ .1 . ~, - ..... ..L..'"t ;:.. -
O· e tc 4. :;
s in~plif ied
c "' e
't,
n
v~. i ... 0.
.if
.4. ........... _
L s
C:O i.-C. tr
e.
:oad':' ...
u"" o",t inea.
.0
1'., _ rve
~l d 1 ...\. .. '"' ~ I... . v ~ .)_....
o
be s tnoe ty iCC1
tnst ll_ ... ..... r...e t.e 51 e r
..e 1;;> •c ~e.r re.
te \,; r. t L ucu.~ \lea. f .t~L~ .. .. I., ~
\;.p' ard e l enc./
also t Co .CO • C. f~or.. '"'
L.t:J <2"C.. - ur. I i:.. ir.f:l te 4- 1e a ave....
..
-
.'
y
-1,-, -
...... . .... ,'re~s
ht•
.ieiskopfl{t:in -e II ,
Yor '.
[al ~, ~hin
Pl'ogre~
..
Yar.g, _ h., " ....i.::>serta 01 :!'e~ enive .ity, l~ ... l.
-1 -
ITIhe tes ts re rted. OIl here:) ... are a
le o. 1 c i''F 40 s del·verea. 14'-v" ...... 6.n
It -.o. 2 8 ,F At' - .. !Laled "_v
If 1"0. 3 8 ,7 ~ e~i~leredTt It
n '0. 4 8 .rF 67 b. ..nealed " tt
C
....eat. D2 ./F 40 ::>' t.ila -:ed. (,; ntinuotl.s e m
If 8 .•F 40 :::>illlulate f an'e3'
" D4 8 'F 40 imulated Jontinuous ueaniS •.~
It B 8 ;rF 40 t1 tt n
B7 14 .J' 30 tt It " -Strai""h
'ormection A 8 b 13 >.Ilee conr........ c ~ion
Tf K 8 B 13 t1 1f
tt 1. 8 B 1~,. It
" 1: 8 .d 13 " t1
- 2-
pFor an exan.ple a cuil t-in oean is used as sho r~ on
P2
Po
P p
fe- .!- b
.~P.
A - B c ..
Load- efle c .. i '"'n vur-v~
In order to f'n the . flec~iont Ge values of Pl , Pa
a d P2 have to oe found which is possible TIit a hbrd~ook.
n oL2
"'1 ab2
l~",L
Pa = ..,9-
PO) - .c.. 0- -....
1 - ~ (f _[~t...::_:.) l )11~ u+,",\f-1A~
• II - f J" en:
d :
d :d.d •• (P -
P2 - "[) )"al~ b a}
10 curves of ~e siIil.le 1 stic hod were sho n ec se
the I ere presented in an e rlier re ort.
--'his . thod i very time consQ~inc a d to rrive at a
satisfuct,ry solution, a nu~ er of trials have to e rna e.
line ffiathematics involv d are very simp] e.lin that the arddS
of e ..-1; curves Cire compllted and tneir eoout
the ee ter line 0 tne ue~:w.
~his ~etnod 's rathe 8 "e'" 8 •• 1 .} •..,e. son:e bee se
-che to tl:il aflec tior. 1... bro} r. p i.t 0 ... 1.' P l·ts aLe. ~ c
part 1'e ui es a great a ount or cc :u:st'on .wor. It i
posst to w rk th's ,et d tle Q ~e ~ ·s n~drieal inte-
'ration mort::: or less f;raphical.,
elovl are the e({ua ti ::m .mien tire nece..,sl:i1'Y for an an-
alytic!::l solu ion. ...·he eflectiOl: is fi"'ure for "he elasti ,
.1aEtic an strail -hBruenin o tiOlL~.
y ='l'he total efl c t i . is '<;' a to:
"111 + (,)1
2+ (y) 13 + di} 12 L-l2-l3)
1s cor p03ed f:
(y)ll di ~. )-,.
( il2 : 4~ V (Fr t a x
(y) +~
'"
C :. + = t,).:) J...
-l'-t-
= 2-6' 7
V"Oj t e :.r.~
.....u....
,L• ...
I d • a " + :x..~ ::... I
3.....
a
b
1. n.a n t
.1 .,'1 . ". -} ~ i .
_....operty of s. ~:' .. _ J.. ... S~ .. J. -
.. 1 i. ..e 1a
of ::ot ....
cf e':&2tic' y
, ex r. Ie o~: t.
t' e r·~'. tor the ot~pr t"eo 'es this .. ',~~d oe very rd •
to solve ....; Vley ..... _·, 'it,. YCJ.~.. t J th c'y, t1e .. 1"::>' r- 0eCCl....es
• c~ctal ef.ecti .,.. is "':'81. - .'" ..... ..v.
0= , \d_ .,. d.J)...'''no "" da
:. d f.!.e :'on 0: t ,- ca!l~'::'evert ..... '-" ~ .
0' = Q':.flec l.~ 0
"
Oa - y + ]2 +',-re' [ ~ 'j, G' - . ~~~= -'- AX --=. _
:r :; ..>Li
- V(L'Y2 - X - X
(I -X.)Y =....
he ... e:
- rr.X = - ( , -
y;•
1 [ .,2 J]L. .... - Z 'l .
~= - ! - .... . l··2 J.oJ ... "a
d - ¢3 L- X0
N :re n< i 9'1'<7-....
ea fI L oit .-1' C lr e
M a -l--...---,,-=-=.--------=====---r-"
M
'*' X AL
f • 0 < •.
for 0 < •
..
•.. ...'
"G)
~~r--
s,
~t:---~
8 2
~,
/ --C. E. 113.
P '.
DE F LE CTIONS OF BEAMS
(s imple be ams . B I and B 2)
I~
- actual-
C!> Weiskopf,
I Il:. num. iIlte"gr.
II/
f.-- .
0.5 1.0 1.5 2.0- .
~ .
10
o
60
40
50
(/)
Cl.. 30~
z
0 20<{
0"-.J
DEFLECTION IN INCHES
•.. .,
60, .
~ ::::==B~
50
~~ B...
/"
40 I(I / C.E.1I3.
Deflect ion of Beams
CflQ.. 30 (simple beams B3 and B 4)- v-~ - actu al
Jf' .'
z. (9 Weisk·opf,
0 208. n u m. int e gr.
<{ /0..J
10 /.
I
of
0.5. \.0
D"EFLECTION' IN INCHES
1.5 2.0
. ' . •.. .'.
2.01.51.0
DE F L ~G T ION IN INCHE S
0.5 '
" -.<
-
~~"
~ L--- B4-
~v---- --------
,-'
/~
82
C.E.113."
~
Deflections of 8eams
(continuous beams 82,4,5).
II'/- act u 01
.~:~:~.;.~; }" 'eo num. inte gr.II', .
H. Yang8
«:> Wp.i!=;konf
,
..
In" k;)
40
10
o
20
50
30
60
z
o<{
o...J
(J)
CL,~
;T
40
o
,l
:
.'y--~
\
1/
I ~ Ba
I~. , .
;)." ..
.. " ~
C.E.113.-. ,.1' f.~i-1;: ,... , ..' .. -,.,'
Deflectio ns of Beams
(simula te d frame 83')
- actualCl nU,m. integr.
/I
,
/
,
. j
(f)
CL
~
za«a...J
i;' ,
60
50
20
10
0.5
. ..... \ l~.
1.0
o E F LEe T ION ' IN INC H E S
1.5 2.0."
G>
~
•... ..
70
60
50
(J)
Q.. 40~
z
~ 30o.-J
20
10
o
~ ,
) V
.~
B,
V "
/17 G. E. 113..
Deflections of. Beams
/ ( con tin 'i: Q.lJ"S be am B 7)".'
- ci ctual
~ num. integr.
8 H. Yang
f 0 We isk'opf
. .
..
.«'
/.
,
O. 5 I. 0 1.5 2. 0
DEFLECTION IN INCHE S
..", '".. . ."
DEFLECTION IN INCHESv
0 /,
~~'7'-
,,/~
l0
v- ~~
~n
~ A -.....0::::::
~0 /
~
/C. E. 113.
Detlection of Knees::T8
C A,K ,L, M ).
II~( connections
_ actual
.. H. Yang
;:Ic
/I~~
O. I O. 2 0. 3 0 4 O. 5 O. 6 O. 7 '0 8 ~
o
20
70
100
60
300
z
. - 50ena..~
I
r0 40z