comprehensive design example

7/25/2019 Comprehensive Design Example

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COMPREHENSIVE DESIGN EXAMPLE FOR PRESTRESSEDCONCRETE (PSC) GIRDER SUPERSTRUCTURE BRIDGE

WITH COMMENTARY(Task order DTFH61-02-T-63032)

SI CUSTOMARY UNITS

S!"#$$ed $oTHE FEDERAL HIGHWAY ADMINISTRATION

%re&ared 'Modesk# a*d Mas$ers+ I*,.

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2.1 Kch thc hnh hc v vt liu s dng

Loi kt cu

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)i( tng kch thc c-( d 9b l gi/ #h v" th(` 9Ei ng sut. @s kh0c nh(u gia( ng

sut khi cng v ng sut ti gi(i 9on cu3iC

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Kch thc hnh hc ca h tng:

D& t&ung gi(nF 6ng nhi%u c't @I c't kho/ng c0ch 1IGH1C 97t t&,n *ng 8w 97t t&,n n%n c0t.j3 j3 ngu`,n kh3i P9;c ch3ng 9x 8yng 't hng cc th4# < t&,n n%n 90. Dng c0nh cha

z h5ng kb t^ 7t s(u 9t 9[#P 8/n u0 9' th 9;c 97t 't 9u k, l,n 3P 't 9u k, l,n8/n d 9x.

Vt liung 9' 8, t]ng

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jodulus 8/n 7t cu }s { 2IAI.B1 je( @AMAI ksiC.3t th4#

)ii hn ch/` t3i thibu c-( c3t th4# thng ?` { I2> je(.3t th4# d ng lc

ng knh 12.N @>.B inchCP 9' ch_ng th# 0c th4# 1M> je(. @2N> ksiC.6in tch t(o th4# W#s { >.1BA in2)ii hn ch/` c-( c3t th4# ?#`{ 1NB je( @2IA ksiC.)ii hn 8%n c-( c3t th4# ?#u { 1M> je( @2N> ksiC.jodulus 9n h|i c-( c3t th4# }#{ 1VN >>> je( @2MB>> ksiC.

Cc thng s khc nh hng !n "ic #h$n tch %&'

Dhi gi(n t&u`%n lc l 1 ng`.' t&ung 8nh l N>.


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-hu*c tnh hnh hc ca %& li/n h0# & ng3)i'

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x w#* (12.6 "") ln chi%u d` c-( 8/n 7t cu Q U chi%u &'ng c-( 8/n c0nh t&,n c-( d chnh

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Ch :

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Chiu d# ca bn m,t cu s dng trong *h@n tch ! chiu d# hu hiu bA Bua !(* -hng ch)u !$cDnh !(* *hEng n(c tch h*F

Giu 78HI ' 30m 3Jt %n cc !an can !i4n h* !i4n tc *hi hKn ch%> ch5 3Jt %n trong trKng thi gi(ihKn -hai thc ' gi(i hKn mAi8 Lhn chM thch 67898:898; gNm cO *h+ng *h* 3"* 35 nh h?ngca !an can !i4n tc trong m,t cPt> bQng cch ch5nh !Ki b rng ca cnh hRng 8


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.4. THIT K BN MT CU.

4.1 Thit k bn mt c!.

\goi 'ic thi%t -% bn m,t cu d(i tc dng ca tYnh ti ' hoKt ti tKi trKng thi gi(i hKn c2ng 8 hoKt ti tc dng !4n bn m,t cu8 Lh+ng *h* th$c nghim th Ei hAi t c&t thJ* h+n &i '(i ') tr bnm,t cu ? *ha trong so '(i *h+ng *h* tnh ton gn Mng Dthe Approximate Method)8


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Nh#n% th,n% - /0! c!:jhong cch dm :HZ mm4 tng bo ' ? m,t tr4n 9H mm D6H8;:8eF

Dk -. %n ;H mm !(* hao mEn tch h*F84 tng bo ' ? m,t d(i :H mm D6H8;:8eF8

i(i hKn ch# ca c&t thJ* 7:Z *aC2ng ch)u nJn ca b4 tng : *a8 s$ qn mEn Dgrinding> groo'ing> sacri_icia!F -hng n4n nhA h+n ;[H mm8 n m,t cumAng h+n th c ch"* thuUn n%u cO s$ thng Bua ca ch u t8 Cho !oKi bn '(i chiu d# bJ h+n ;p:Znh)* bn thi%t -%> cn 30m 3Jt n4n cho d$ Sng !$c 'o h(ng nh)* bn n# . -i.m sot nSt8

`u h%t c+ Buan th]m Bu#n th Ei hAi mt thi%t -% bn m,t cu d# t&i thi.u :ZH mm Dbao gNm ;Hmmca !(* hao mEn tch h*F

Cng th4m Bu# )nh bn m,t cu d# t&i thi.u nh iu 68[8;8;> mt 'i c+ Buan th]m Bu#n th -i.m trachiu d# ca bn m,t cu s dng iu 6:8H8:898e 8 Giu -hon trong mc n# !m trung gian gia cc!oKi bn m,t cu> ' mc ch ca chMng ! gi(i hKn 'ng d(i tc dng ca hoKt ti8 ic * dngnhng iu -hon n# cho 'ic thi%t -% bn m,t cu th hi%m -hi -i.m sot 'ic thi%t -%8

trX -hi mt chiu d#nhA h+n k th nghim thAa mkn 'a chKm 30 c 'o !an can8


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i thi%t !an can !oKi > -ch th(c ca !an can th ch5 trong hnh 7f:8 6Sc ch)u 'a cham ca !an can thc 3c )nh s dng iu -hon D6^;e8e8;F 8 \hng ,c tnh ca !an can ' -h nqng ch)u 'a chKm thc tOm tPt nh sau8

Ch5 s& chung ca !an can ' -ch th(c !an can8

4^# 8 s& sch ! \o8;eZ9;>

`nh 7f: inh h1a m,t cPt ngang ca !an can8jh nqng ch)u ti tr1ng ca !an can th !(n h+n #4u cu t&i thi.u cho b?i ti4u chu]n8 ng bn m,t cucnh hRng th c Ei hAi thi%t -% cO -h nqng ch)u ti !(n h+n -h nqng ch)u ti th$c ca !an can b4 tng8

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-hon cho m,t cPt b4 tng c&t thJ* ' cO th. +n gin hOa cng thSc trong tr2ng h* n#8Cho m,t cPt hnh ch nhUt> chiu cao ca *hn m,t cPt ch)u nJn ! c th c 3c )nh s dng cng thSc6H8[8e8;8;f78

'rong *Aps + di,n t-ch thp d/ 0ng l/c (mm2)p$ + cng ko 5$" nh ca thp d/ 0ng l/c (M8a)p" +gi9i h:n ch;" ca thp d/ 0ng l/c (M8a)As +


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'rong *ps + 0ng s$Pt tr$ng =nh trong thp d/ 0ng l/c ca s0c khDng $n(M8a)

Q5. S&.7.3.1.1R1ds + kho;ng cDch tE th9 ch$ nn ngoFi cGng Hn trIng tJm ca thp ch$ ko khngd/ 0ng l/c (mm)dTs + c/ l" tE th9 ch$ nn ngoFi cGng Hn trIng tJm ct thp ch$ nn (mm)= +=> rng ca m?t ch$ nn ca cP$ ki,n (mm)=! + => rng =Kng ho?c ng k-nh ca m?t c@t hnh trLn (mm)h + cDnh ch$ nn ca m?t c@t hnh # F hnh ' (mm)Cho m,t cPt b4 tng c&t thJ* hnh ch nhUt -hng cO du! ' -hng cO c&t thJ* ch)u nJn cng thSc tr4nc rMt g1n !Ki thnh8

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.KiQm t?7 6#Rn% ct thS& ti thiQ! 3 ti )7.

V$a 'o -inh nghim ca Bu -hS !ng c&t thJ* t&i thi.u ' t&i a th cha tXng -i.m sot 'ic thi%t -%bn m,t cu8 C&t thJ* t&i thi.u th c trnh b# nh iu H8[8e8e8:8 \hng iu -hon n# th gi&ng trongnhng ti4u chu]n ^^6` chMng cTng c minh h1a . ng2i ng2i s dng Bu0n '(iBu# )nh n#8ji.m tra chiu cao ca -h&i nJn8

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.u rQng thng s& b rng '%t nSt cho iu -in -hPc nghit th s dng cho 'ic !oKi trX -h nqng*hn c&t thJ* d(i P# -hng c ch0 *h -hi bqng cO mu&i tan ch# !1c Bua bn m,t cu8 t 'i c+Buan th]m Bu#n th s dng tr) s& cho 'ic thi%t -% *hn c&t thJ* ? P# bn m,t cu> trX tr2ng h* bnm,t cu ? mi tr2ng bi.n8 ic !m n# nhQm mc ch !m cho c&t thJ* ? *hn P# th -hng ti%* 3Mctr$c ti%* '(i tc dng ca mu&i8 6$ -hc nhau ' th. hin nh din d)ch tr4n th hi%m -hi nh h?ng %n'ic thi%t -% b?i ' Sng su"t t&i a cho c&t thJ* P# '(i :Hmm b4 tng bo ' th -i.m sot bQng gi(i hKn

Z89 _# ' sv -hng /i n%u gi thi%t trong mi tr2ng bnh th2ng8ng su"t ? ti tr1ng s dng8 (Sp..1)

nh #4u cu 6H8[8;F8i s trc trung hEa th cO -hong cch # tnh tX m,t ch)u nJn ca m,t cPt8i thi%t b rng ca m,t cPt th bQng -hong cch ca c&t thJ* ;[ mmVin tch c&t thJ* chu#.n /i th bQng Ddin tch thJ*F8Dh s& modu!usF :ZZDF ;9ZZ mm :8C@n bQng *h+ng trnh mom0nt tYnh

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.;9ZZ8D;H[f#F ;[8#8D#p:F

ii *h+ng trnh tm ra c # 7Hmmom0nt Bun tnh chu#.n /i = trans_orm0d ;9ZZ8D;H[f7HF :};[8D7HeFpe 2.pv X 10""

ng su"t trong c&t thJ* -V 9McWI -hi O ! mom0nt tc dng !4n ;[mm b rng bn m,t cu8s x ~(36 2X1vX112){2.pv X 10v x 22.1 M&a

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O4.X Thit k M=m>nt Am cY7 bn mt c! ch= nhZn% (m %iZ7.7. H=t ti.


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.\h gii thch tr(c @#> Sng su"t ? thi gi(i hKn s dng th c tnh ton s dng h s& modu!ar n 8om0nt tYnh ti ? trKng thi gi(i hKn s dng tKi m,t cPt thi%t -% cho mom0nt @m ') tri gia nh)* fHe:\fmmpmm8

`nh 7fHa> C&t thJ* -i.m sot nSt do mom0nt @m d(i tc dng ca hoKt ti8om0nt do hoKt ti tKi m,t cPt thi%t -% &i '+i nh)* trong -% cUn nh)* bi4n f; 79Z \fmmpmm8


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`nh 7fHb c&t thJ* -i.m sot nSt do mom0nt @m d(i tc dng ca hoKt ti8

4.1\ Thit k bn mt c! c'nh h5n%.

H]nh 4.; -ch th(c *hn cnh hRng ' 30 ti

i thi%t *hn P# ca bn m,t cu 'ng hRng th th"* :H mm so '(i *hn # ca cc nh)* bn mc -hcnh hnh 7f98 j%t Bu th t/ng chiu d# *hn hRng bQng :eZ mm8 Giu n# th th2ng cO ch trong 'icch&ng !Ki tc ng ca 'a chKm 30 c8


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. cO th>= &h#$n% n%7n%.9a1.4.1 c s dng cho trKng thi gi(i hKn ,c bit (S1.3.2.1).

ho,c i Z8H cho cu cO 'ai trE t Buan tr1ng h+n8


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.d x oer4a*9 sa! $4#,k*ess $o& ,oer !ar d#a"e$er x 230 6p (16)

x 1p ""#= $4#:$ ,^$ $4& ,5 x 1.p ""2{"" (1)ic -i.m tra hm !ng c&t thJ* t&i a th -hng - '1ng sv -i.m sot 'ic thi%t8 b?i ' cngth4m c&t thJ* ? *hn cnh hRng> n4n thUn tr1ng -hi ti%n hnh -i.m tra> s dng Bui )nh 6H8[8e8e8;Chiu cao hiu Bu ca m,t cPt h ;H[ mmDu rQng chiu d# cnh hRng th d# h+n :H mm cng th4m chiu d# &i '(i #F8Cho m,t cPt d(i mom0nt ' !$c -Jo d1c trc L> sSc -hng u&n danh )nh n th c tnh ton nh sauI

n th *hn on ' - thuUt th c s dng . 3c )nh chiu d#bn m,t cu d# h+n c s dng8

'a chKm !an can th c *h@n b& tr4n mt chiu di c &i '(i mom0nt 'c}:` cho !$c d1c trc8 Giu n# bPt nguNn tX ngu#4n nh@n ! chiu di *h@n b& sv gia tqng> gi tr) gOc*h@n b& th -hng c ch5 ra trong ti4u chu]n ' c *hn on bQng - thuUt8 nh hnh 7f 8 t 'i thi%t -% thgi thi%t gOc *h@n b& ! 7H > gOc n# cTng c ch"* thuUn8

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V> *ara*0t 8H;D[; ;eF [e \fmmpmm

V> x6 ;87[; 3 ;ZfeD:ZHF:p: e; \fmmpmmom0nt cO nh@n h s&

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h, ,t$ $4#:$ k: x RE{~, y 2H y 2(0.p)u x 610 3pp{~pw y 2(106p) y2(0.p)(20p)

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c. KiQm t?7 m=m>nt (= t[nh ti 3 7 `> ti mt ct CC nh# h]nh 4E.

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2)'-nh Hn tE =iHn F co ngt s` dKng trng hWp ?c =i,t cho dZm t:i thiiYm ni liVn tKc. %Dch tiHp cCn nF" th "V$ cZ$ xDc nh hi,$ 0ng ca tE =iHn F congt cho hai trng hWp khDc nha$* mt =;n m?t cZ$ O trVn mt dZm tXng i cF mt =;n m?t cZ$ O trVn mt dZm tXng i m9i. Mt trng hWp theo sa$ cai,c tiHp cCn nF" lF =ang 8enns"lania. ai t$Oi ca dZm Wc gi; nh trong thiHt kHlF 3] F 4&] ngF".'rong trng hWp t$Oi ca dZm th Wt 5$a gi9i h:n_ hi,$ 0ng catE =iHn F co ngt th Wc phJn t-ch l:i tr9c khi xJ" d/ng Y ch@c ch@n rngkhng

c ;nh hng phXng h:i nFo (no detrimental ewects)trVn cP$ trc.C4o / d *+ =*4 48>*9 ,a $ !#:* ,o *9$ $4[ ! @a. T *4#*+ ,4o ", ;/,4$4a" k4=o+ $/*4 $oQ* $ !#:* ,o *9$ $4[ ;8.9 M~T MT {NG SUT. (S>..>)>.9.1 T}n g+$n.MPt mDt 0ng s$Pt c thY Wc m t; nh lF mPt mDt t0c thi F mPt mDt theo thigian. MPt mDt 0ng s$Pt do l@p ?t neo_ do ma sDt F co ng@n Fn hi lF mPt mDt t0c

thi. MPt mDt do tE =iHn_ co ngt F t/ trGng (relaxation) th theo thi gian.%ho nhBng cP$ ki,n cvng tr9c_ mPt mDt 0ng s$Pt lF do* co ng@n Fn hi_ co ngt_ tE=iHn F t/ trGng ca ct thp. %ho thFnh phZn Wc thi cng F d/ 0ng l/c mt giaio:n_ 5$an h, cho 0ng s$Pt t0c thi tr9c khi tr$">n l/c cvng_ mPt mDt 0ng s$PtWc lP"*

p' + pQS y pS y p% y p2 (S&..&.1R1).'rong

pQS + MPt mDt do co ng@n Fn hi (M8a)pS + MPt mDt do co ngt (M8a)p% + MPt mDt do tE =iHn (M8a)

p2 + MPt mDt do t/ trGng ca thp sa$ khi tr$">n l/c cvng (M8a).$ f rng mt mPt mDt 0ng s$Pt cng thVm x$Pt hi,n s$t thi gian ko ct thp Ftr$">n l/c cvng. 'hFnh phZn nF" lF mPt mDt do t/ trGng ca ct thp t:i lc tr$">nl/c_p1.i9i h:n 0ng s$Pt cho tao thp d$l ca cP$ ki,n cvng tr9c (pretensioned mem=ers)Wc cho trong i>$ S&..3 cho 0ng s$Pt t0c thi lc tr$"Yn l/c. UY xDc nh 0ng s$Ptkhi cvng (zacking stress)_ mPt mDt do t/ trGng t:i lc tr$">n l/c_ p1_cZn ph;i Wc

p2


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.cng thVm Fo gi9i h:n 0ng s$Pt mKc S&..3. 'rong th/c hFnh_ khDc nha$ tE giaio:n nF" Hn giai o:n kia C" 0ng s$Pt trong = thp nFo th Wc ch\ ra trong =;nj. 'iV$ ch$n gi; thiHt rng ngi thiHt kH sj xDc nh 0ng s$Pt trong nhBng = ctthp nga" tr9c khi cvng ko. NhF s;n x$Pt th c trDch nhi,m xDc nh l/c cvng (thezacking orce) =ng cDch cng thVm mPt mDt do t/ trGng lc tr$">n l/c_ mPt mDt dothiHt = cvng k-ch F mPt mDt do ,m neo Fo 0ng s$Pt t0c thi nga" tr9c khitr$">n l/c do k{ s xDc nh. U l9n ca mPt mDt 0ng s$Pt do thiHt = tr$">n l/c cvng

F mPt mDt do ,m neo phK th$c thiHt = tr$">n l/c F c0ng ca neo Wc s`dKng =|i c dZm. % mt kiHn ngh* k{ s thng 5$a nhBng t-nh toDn sX = Y xDcnh 0ng s$Pt tr$">n l/c mong Wi.

$ S&..&.3.iD tr ch0a /ngtrong phXng phDp =ao gm mPt mDt 0ng s$Pt do t/ trGng t:i lc tr$">n l/c_ p1.UY xDc nh mPt mDt 0ng s$Pt phK th$c thi gian sa$ khi tr$">n l/c cvng i 9ithFnh phZn d/ 0ng l/c cvng tr9c_ p1 cZn Wc 9c lWng F trE i tE tOng mPt mDt0ng s$Pt theo thi gian t-nh toDn s` dKng i>$ S&..&.3.

p3


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.8hXng phDp ch-nh xDc ('he rened method)cho t-nh toDn mPt mDt 0ng s$Pt phK

th$c thi gian th Wc trnh =F" t:i i>$ S&..&.4. 8hXng phDp nF" th m t; trVnF Wc s` dKng trong - dK nF".

8hXng phDp 9c lWng mPt mDt 0ng s$Pt i 9i nhBng d/ 0ng l/c tEng phZn_nhBng th0 tXng t/ cho d/ 0ng l/c toFn phZn_ Wc tm t@t (m t;) i>$ S%&..&.1.

>.9.! T0n ,%n n +, @$n &*+ n$a ,-7 8 ,-+a=n ..5).

&$

y &S

x 0.p&

x 0.p(1v60) x 13wp M%a.>.9.5 X &Qn 6, 6, n +, , ,8 (8n,$n,$n%+ ..>.!)M, 6, % 6$ , (S>..>.!.!)uh; nvng mPt mDt 0ng s$Pt d$" nhPt i 9i dZm cvng tr9c lF thiHt = giB x$ng(holdRdo!n deices) cho nhBng cDp d$l xiVn (draping or harping tendons). 'iV$ch$n < ch\ r i,c nhn nhCn nhBng mPt mDt nF".C4o / d *+ $$ ,= ! $4& $4[ $4*9 $4#:$ ! 9# X^*9 $4[ k4B*9 ;8..>.!.5)MPt mDt 0ng s$Pt do co ng@n Fn hi trong cP$ ki,n cvng tr9c th Wc lP" =ng0ng s$Pt =V tng t:i trIng tJm ca thp dl t:i lc tr$">n l/c cvng_ cgp_ nhJn =i h,s giBa mod$l$s Fn hi ca thp dl F mod$l$s Fn hi =V tng t:i lc tr$">n l/c.

Ui>$ nF" trnh =F" trong cng th0c Q5. S&..&.2.3aR1.pQS + (QpQci)cgp (S&..&.2.3aR1)'rong *

cgp + tOng 0ng s$Pt ca =V tng t:i trIng tJm ca cDp do d/ 0ng l/c tr$">nFo lc cvng cDp F tnh t;i =;n thJn cP$ ki,n t:i m?t c@t c moment l9n nhPt(M8a)

Qp + mod$l$s Fn hi ca thp 0ng s$Pt tr9c (M8a) Qci + mod$l$s Fn hi ca =V tng lc tr$">n l/c cvng (M8a)

p dKng ng th0c nF" "V$ cZ$ 9c oDn 0ng s$Pt trong = thp sa$ khi tr$">n l/c.9c t-nh d/ kiHn cho thFnh phZn d$l th Wc cho =i i>$ S&..&.2.3a.Mt cDch khDc_ mPt mDt do co ng@n Fn hi c thY t-nh toDn s` dKng cng th0c Q5.%&..&.2.3aR1

'rong *

e%+ lVch tJm tr$ng =nh ca thp d$l t:i giBa nhp (mm)p=t + 0ng s$Pt trong thp d/ 0ng l/c nga" thi iYm tr$">n l/c cvng nh ch\ r=;ng S&..3R

].7&p$ (M8a)Mg + Moment t:i giBa nhp do tnh t;i =;n thJn ca dZm (NRmm).

>.9.5 X &Qn n +, $ ,:; n


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.&$ x b*9 s$ K, $rV* h, (Stress immediatel" prior to transer) &S

x 13wp w.0x 1301 M%a.>.9.> T0n ,%n .9.!.5.5"1 # ' 6 ,-+n @n n n6 ,0n @n ;*n ,-6.

T/*4 $oQ* "$ "Q$ b*9 s$ do ,o *9$+ &SR

C4o W*9 A$a*$a+ eor9#a+ > ; 9#= $4#:$ ; G" $r*9 ![*4 *Z" $4[ ;8.9..! M, 6, % ,| @8n (S>..>.9.5)


56/136

.cdp_F Wc cho =i cng th0c S&..&.4.3R1. p% + 12.]cgp 7.]cdp ] (S&..&.4.3R1)'rong *

cgp + 0ng s$Pt =V tng t:i trIng tJm ca thp d$l lc tr$">n l/c (M8a)cdp + s/ tha" Oi 0ng s$Pt =V tng t:i trIng tJm ca thp d$l do t;i trIng dFih:n_ ngo:i trE t;i trIng tDc dKng t:i thi iYm th/c hi,n d 0ng l/c. iD tr ca

cdpnVn Wc t-nh toDn t:i cGng m?t c@t ho?c t:i nhBng m?t c@t t-nh toDn cgp(M8a).iD tr cdp =ao gm hi,$ 0ng t;i trIng ca dZm ngang_ =;n m?t cZ$ l9p $t(ha$nch) lan can_ l9p ph trong tXng lai_ ti,n -ch ($tilities) F nhBng t;i trIng dFih:n khDc_ other than nhBng t;i trIng x$Pt hi,n lc tr$">n l/c t:i m?t c@t xem xt_ thWc Dp dKng cho cZ$.T/*4 $oQ* "$ "Q$ do $ !#:* &CR.uQ, ;*4 b*9 s$ $ro*9 ! $B*9 $P# $rf*9 $m" ,a $4a*4 d K, $rV* h, ,Z*9+ ,9&.

%h f rng thFnh phZn th0 2 trong c; phZn t` F m$ s trong phXng trnh trVn chot-nh toDn cgp d/a trVn th$c t-nh m?t c@t 5$" Oi (the transormed sectionproperties). '-nh toDn cgp s` dKng th$c t-nh m?t c@t ng$"Vn ca m?t c@t =V tng thcng Wc chPp nhCn_ nhng sj cho kHt 5$; 0ng s$Pt =V tng cao hXn F _ kHt5$;_mPt mDt 0ng s$Pt cao hXn. a = thFnh phZn th0 hai nF" tE c; phZn t` F m$s ca phXng trnh trVn th cho ra 0ng s$Pt d/a Fo m?t c@t ng$"Vn ca =V tng(the gross concrete section properties).#Q $r ,9& , $4J XQ, ;*4 s d*9 4a# &48?*9 &4Q& k4Q,l

1) S d*9 ,B*9 $4b, $8?*9 $h $r* ;c$ b*9 s$ $ro*9 ! $4& !`*9 b*9s$ sa k4# $rV* h, (1301 M%a) $4a o ; b*9 s$ 9#a# ;oP* $b, $4L# $rV*h, (0.p& x 13wp M%a) ;J 9#Q $r ,a " ,4*9 !`*9 1.0.

2) '># [ sh $4a ;j# !#:* dP*9 ,a ! $B*9 s^$ @Q $r[*4 ,Z*9 (!#:* dP*9 $b,$4L# K, $rV* h, ,Z*9 ,*9 $r !#:* dP*9 $b, $4L# sa k4# $rV* h,) $4[ !`*9 sh$4a ;j# !#:* dP*9 $ro*9 s


57/136

.; $/*4 $oQ* > $r* (sh k4Q, *4a do " $r|* s^)

uQ, ;*4 ,d& *48 ;*4 *94a $r*.,d& x ~(Md#a y Msa!)ep.p{I9 y ~(M&ara&e$ y MFS)(N.A.!ea"!o$ CS&s){I,,d& x ~(1.v1X10vy 2.2wwX10w)(w){3.0p2X1011y ~(2.23X10vy 3.010X10v)(130w

12){p.62X1011

,d& x 2.2 M%a.T/*4 $oQ* ;8.9..5 S `n n +, (S>..>.9.9)Tj*9 s^ $h $rW*9 $P# !$ k $4L# ;#J" $rV* h, $4[ !ao 9" 4a# $4*4 &45*l $h ,4W*9$P# $4L# ;#J" $rV* h, sh $rW*9 $P# $4L# ;#J" sa k4# $rV* h,.Sa k4# $rV* h, (Sp.w.p..,)lM, Sp.w.p.., ,*9 ,& &48?*9 $r[*4 ,a #, 8, 8


58/136

.T/*4 $oQ* ;8 MP$.*9 s$ $P# ;#J" k/,4+ & x b*9 s$ $b, $4L# K, $rV* h, y "$ "Q$ do $h $rW*9$P# $rV* h,

Th $rW*9 $P# $4L# ;#J" $rV* h, (Sp.w.p..!) M$ "Q$ &4 $4, $4L# 9#a*.

Ni ch$ng_mPt mDt do t/ trGng t0c thi th xDc nh =i nhF s;n x$Pt. ngi k{

s th "V$ cZ$ lFm mt 9c lWng c lCp > mPt mDt do t/ trGng_ ho?c l/a chIn nhi>$ c$ng cPp mKc S&..&.1_ nhng 5$" nh ca i>$ kho;n nF" th s` dKng nh lFmt s/ h9ng dn. NH$ thng tin d/ Dn cK thH th khng c sn_ giD tr ca pz c thYWc lP" ].]p$ cho mKc -ch ca t-nh toFn nF". %ho - dK nF"_ pz sj Wc lP" ].7&p$.MKc S&..&.4.4= c$ng cPp phXng trnh Y 9c lWng t/ trGng t:i lc tr$">n l/c chodZm cvng tr9c_ 0ng s$Pt =an Z$ Wc t:o Wt 5$D &] cng ko 5$" nhca = thp_ p$.%ho tao thp c t/ trGng thPp*

'rong *t + 9c lWng thi gian =ng ngF" tE lc t:o 0ng s$Pt Hn lc tr$">n (da"s) gi;

nh lF 1 ngF" cho - dK nF".pz +0ng s$Pt t0c thi trong = thp t:i thi iYm c$i ca tr$">n l/c(Fo c$i

lc ko) (M8a) gi; thiHt =ng 1413 M8a cho - dK nF".p" + gi9i h:n ch;" ca thp d/ 0ng l/c (M8a)

Do ;+ b*9 s$ $P# ;#J" k/,4+ & x 13wp y 1.3 x 10w.3 M%a>.> {NG SUT TRONG TAO THkP DL.

>.>.1 {n +, ,-%n ,$% ,:; n +, ,-7 ,8 n +n $n &Qn.

ng s$Pt trong thp d$l t:i s0c khDng $n danh nh c thY xDc nh s` dKng phJnt-ch 0ng s$Pt th-ch hWp. 'ha" cho phJn t-ch nh C" mt phXng phDp Xn gi;n thtrnh =F" S&.7.3.1.1. 8hXng phDp nF" th Dp dKng cho m?t c@t hnh chB nhCt ho?cm?t c@t 5$a cDnh cho $n mt trKc phJn phi khi 0ng s$Pt hitne" Wc ch\ ra S&.7.2.2 th Wc s` dKng_ theo 0ng s$Pt hB$ hi,$ trong thp d$l cLn l:i sa$mPt mDt pe_ th khng nh hXn ].&p$. ng s$Pt tr$ng =nh trong thp d$l_ ps_ c thY

Wc lP"*&s x &~1 k(,{d&) (Sp..3.1.1-1)Tro*9 ;l

k x 2(1.0 & {&) (Sp..3.1.1-2)#Q $r nk , $4J $/*4 $oQ* s d*9 &48?*9 $r[*4 $r* $4[ dha $r* oP# $4, $/*4,a $4& db ;8


59/136

.

C4o "c$ ,t$ b*9 X 4[*4 ,4 *4\$ (@. Sp..3.1.1-)l

Mc$ ,t$ T > ; $r, $r*9 4|a ;c$ > ,Q*4+ #.e.+ #Q $r n, $4[ *4 4?* ,4#V d !=*+$4[ ;8$ dF" =;n (l9p phLng n9c t-ch hWp th = 5$a)_ php t-nhcho qc ph;i Wc l?p l:i gi; thiHt 0ng s` m?t c@t ' theo nhBng =9c sa$*

1) i; thiHt trKc tr$ng hLa nm trong =;n cDnh dZm F t-nh toDn giD tr qc.%ho t-nh toDn nF"_ => rng =;n cDnh F di,n t-ch nVn ch$"Yn Oi =ng cDch nhJn =>rng cDnh 9i h, s mod$l$s giBa dZm 0ng s$Pt tr9c F =;n =V tng. b> rng =;ncDnh trong cng th0c t-nh qc sj tha" thH cho s` dKng => rng cDnh ch$"Yn Oi qtheewectie conerted girder ange !idth. NH$ t-nh toDn giD tr qc Wt 5$D tOngchi>$ dF" ca =;n F chi>$ dF" cDnh dZm_ tiHp tKc th/c hi,n =9c kH tiHp. NH$khng th_ s` dKng giD tr | t-nh toDn tr9c ca qc.

2) i; thiHt trKc tr$ng hLa th nm 9i =;n cDnh ca dZm cvng trWc F t-nhtoDn giD tr qc. 'hFnh phZn q].& c1(= =!) trong t-nh toDn nVn chia ra lFm haiphZn_ mt cho s/ phJn = ca =;n m?t cZ$ ca m?t c@t liVn hWp F cDi th0 hai thcho phJn = lVn =;n cDnh ca dZm liVn hWp

&s x &~1 k(,{d&) (Sp..3.1.1-

1) x 1v60~1 0.2v(13w{1vvv) x 1v21. M%a.

>.>.! C8=+ 8 ,-+a=n / 8=+ 8 ;, ,-8Zn (T-$n- $n /


60/136

.T *4*9 $/*4 $oQ* $r8,l

&s x 1v21. M%a ('8, $4#:$ k: p..v)&e x 1122 M%a ('8, $4#:$ k: p.p.1)

T ;#V Sp.11..2+ x 1.6 ,4o ,^$ $4& d/*4 !Q" $o* &45*.(32 sn l/c (the transer length).iBa chi>$ dFi tr$">n l/c F chi>$ dFi phDt triYn_ l/c tao thp c thY gi; nh giatvng theo kiY$ para=olic (para=olic manner)_ :t t9i s0c ko ca tao thp chi>$ dFiphDt triYn.UY Xn gi;n t-nh toDn_ mt Fi cX 5$an thm 5$">n gi; thiHt rng 0ng s$Pt tvngt$"Hn t-nh giBa chi>$ dFi tr$">n l/c F chi>$ dFi phDt triYn. i; thiHt nF" th Wc s`dKng trong - dK nF".

N48 ; ,4q $ro*9 4[*4 2-p 4[*4 2-6+ "7# d5" ,48a !a *4" $ao $4&l N4" 1l 32 $ao k:$ d/*4 $o* &45*+ #.e.+ ,4#V d# k:$ d/*4 !t$ ;5 230 ""!* *9o# $r, $#" 9^# ,a d5" k4B*9 #* 4


61/136

.

H[*4 p.p-1 #s a 9ra&4#,a re&rese*$a$#o* o Ta!e p.p-1.

61


62/136

.

+ + - i#J" !t$ ;5 d/*4 !Q" ,a *4" $ao $4& 1+ 2+ a*d 3+y+ yy+ yyy - i#J" k:$ $4K, d/*4 !Q" ,a *4" $ao $4& 1+ 2+ a*d 3+ "$ ,Q,4 $8?*9 b*9

T$@.>"1 (%n,.) # P-,-8n S,-$n F%-

62


63/136

.

+ + i#J" !t$ ;5 d/*4 !Q" ,a *4" $ao $4& 1+ 2+ a*d 3+y+ yy+ yyy i#J" k:$ $4K, d/*4 !Q" ,a *4" $ao $4& 1+ 2+ a*d 3+ "$ ,Q,4 $8?*9 b*9

63


64/136

.

F8+- >.>"1 # P-,-8n S,-$n F%- S%n G-$;8$


65/136

.

C4#V d# $rV* h, x 62 ""C4#V d# &4Q$ $r#J*+ !o*ded x 331 ""C4#V d# &4Q$ $r#J*+ de!o*ded x 16 ""

F8+- >.>"1 (%n,.) # P-,-8n S,-$n F%- S%n G-$;8$.9 T0n ,%n n +, , ,:;.

h, ,Z*9 $P# $#" ,a 9^# sa "$ "Q$ d8# S d*9 4oc, ,8L*9 ;.C4q *4" $ao $4& 1 $4[ d/*4 !Q" $P# "c$ ,t$ *. ' @a *4" $ao $4& 2

3.4o=*9 ,Q,4 !t$ ;5 d/*4 !Q" ,4o *4" $ao $4& 1 x 230 "" ,4#V d#

$rV* h,.%45* $rZ" h, ,Z*9 &4Q$ $r#J* $ro*9 *4" $ao $4& 1 x 230{(,4#V d# $rV*

h,) x (230{62)(100) x 30

*9 s$ $ro*9 $ao $4& x 0.3(1122) x 336.6 M%ah, $ro*9 $ao $4& $P# "c$ ,t$ x 32(wv.1)(336.6) x

1.063 X 106N h, ,Z*9 $P# "c$ ,t$ 33p3 "" $/*4 $ $#" ,a 9^# sa "$ "Q$ d8# ;#V k#*

s d*9C4q *4*9 $ao $4& 1 a*d 2 $4[ d/*4 k:$ $P# "c$ ,t$ *. ' @a *4" $ao $4&

3.C4#V d# d/*4 k:$ ,a *4" $ao $4& 1$r8, "c$ ,t$ * $4[ * 4?* ,4#V d#$rV* h,. do ; h, ,Z*9 $o* ! X$ 4#* $ro*9 *4" $ao $4& s^ 1.

h, $ro*9 *4" $ao $4& 1 x 32(wv.1)(1122) x 3.p X106N.4o=*9 ,Q,4 !t$ ;5 d/*4 k:$ ,a *4" $ao $4& 2 x 30p "" ,4#V d#

$rV* h,.%45* $rZ" h, ,Z*9 &4Q$ $r#J* $ro*9 *4" $ao $4& 2 x 30p{,4#V d# $rV*

h,.x (30p{62)(100) x 0

*9 s$ $ro*9 *4" $ao $4& 2 x 0.(1122) x v.v M%a

6p


66/136

.h, $ro*9 *4" $ao $4& 2 $P# "c$ ,t$ x 6(wv.1)(v.v) x 2.6pv X 10pNTj*9 h, ,Z*9 $P# "c$ ,t$ * x 8, $ro*9 *4" 1 y h, $ro*9 *4"

2x 3.p X 106y 2.6pv X 10px 3.v10 X 106

N Sb, k4Q, * *4$ ,a *4*9 $ao $4& > k4= *Z*9 ,4 ^* da*4 ;*4 $P# "c$

,t$ 213 "" $/*4 $ $#" ,a 9^#

C4q *4" $ao $4& 1 $4[ ;8..1.! T0n ,%n n +, ,8


67/136

.

Bn >."1 # n +, ,8 &in / &a $ *6 (""2)e x k4o=*9 ,Q,4 9#a $r, $r*9 4|a ,a d5" ,48a #* 4


68/136

.M9 x Mo"e*$ do $*4 $=# !=* $4m* d5" (N-"")

ue" "c$ ,t$ 2.2 ,4o $4, $/*4 ,a "c$ ,t$.T/*4 $oQ* $P# $r/ p33 "" $ $#" ,a 9^# (62 "" $ ;5 d5")*9 s$ $P# ;q*4 d5"l

x 3.1 M%a 9## 4P* b*9 s$ ko (3.3 M%a) O*9 s$ $P# ;Q d5"l

x -1p.1 M%a 9## 4P* b*9 s$ ** (-1w.v M%a) OT/*4 $oQ* $P# $r/ 33p3 "" $ $#" ,a 9^# (3pv3 "" $ ;5 d5")

*9 s$ $P# ;q*4 d5"l $o& x -%${A9 y %$e'{S$ M9{S$

x 1. M%a S$ress #"#$ or $e*s#o* (3.3 M%a) O

*9 s$ $P# ;Q d5"l

x -1.2 M%a S$ress #"#$ or ,o"&ress#o* (-1w.v M%a)OT/*4 $oQ* $P# $r/ 16 612 "" $/*4 $ $#" ,a 9^# (16 v0 "" $ ;5 d5") 9#a*4& ,a d5" ,48a #* k:$ (No*,o"&os#$e 'ea").*9 s$ $P# ;q*4 d5"l

$o& x -%${A9 y %$eC{S$ M9{S$

x -1. M%a 9## 4P* b*9 s$ ** (-1w.v M%a) O

*9 s$ $P# ;Q d5"l!o$$o" x -%${A9 %$eC{S! y M9{S!

x -1.6 M%a 9## 4P* b*9 s$ ** (-1w.v M%a) O

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.khDc nha$ giBa tr:ng thDi gi9i h:n # F tr:ng thDi gi9i h:n ### lF tr:ng thDi gi9i h:n # ch, s t;i trIng lF 1.] cho ho:t t;i trong khi tr:ng thDi gi9i h:n s` dKng ### c h, s].. Nh ch\ ra phZn &.3_ mt Fi cX 5$an ch0c nvng th khng =ao gm hi,$ 0ngtE =iHn F co ngt trong thiHt kH dZm cvng tr9c. NhBng t-nh toDn trnh =F" dJ" thkhng =ao gm moment do tE =iHn F co ngt. NH$ tE =iHn F c ngt Wc "V$ cZ$=9i tiV$ ch$n ca cX 5$an ch0c nvng_ hi,$ 0ng ca n th Wc kY Hn. em mKc&.3 F phK lKc % cho i,c t-nh toDn F giD tr ca hi,$ 0ng tE =iHn F co ngt cho -

dK t-nh toDn cZ$.>..!.1 G878 n n +,.

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Co"&+ !ea" 2 x -0.p(,) x -0.p(2) x -1v.w M%aT !=*9 Sp.w..2.1-1+ 9## 4P* b*9 s$ ,a ! $B*9 d8 b*9 h, > $rP*9 $4Q# 9## 4P*s d*9 sa "$ "Q$ ,4o , k#* dh b*9 h, $o* &45* k4B*9 &4=# Xm dh*9 &4m*;oP* do 4oP$ $=# ,*9 # $j*9 d8 b*9 h, 4 4# ,Q, $=# $rf*9 $48L*9X* $4[ ;8


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72/136

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p.6.2.2. T/*4 $oQ* $P# $r/ 33p3 "" $/*4 $ $#" ,a 9^# (3pv3 "" $/*4 $ ;B# d5")

*9 s$ $=# ;q*4 d5" d8# $j*9 $=# $rf*9 (Ser#,e I)l$o& x -%${A9 y %$e'{S$ MDNC{S$ MDC{S$, MC{S$,

x -p.6 y v.wpw p.030 0.23 1.0v3x -2.v M%a b*9 s$ ** 9## 4P* d8# $o* ! $=# $rf*9 (-2p.2 M%a) O*9 s$ $P# ;q*4 d5" d8# $Q, d*9 ,a d8 b*9 h, sa "$ "Q$ $*4 $=#l

$o& x -%${A9 y %$e'{S$ MDNC{S$ MDC{S$,

x -p.6 y v.wpw p.030 0.23x -1.v M%a *9 s$ ** 9## 4P* d8# $Q, d*9 $=# $rf*9 d# 4P*

(-1v.w M%a) O*9 s$ $P# ;q*4 d5" d8# $Q, d*9 ,a y (%S y D) sa "$ "Q$ b*9 s$l

$o& x -%${A9 y %$e'{S$ MDNC{S$ MDC{S$, M{S$,

x -2.23 y .v0 2.p1p 0.122 1.0v3 x

x -2.0 M%a *9 s$ ** 9## 4P* d8# $Q, d*9 y (D y%S)x(-16.v M%a)O

*9 s$ $P# ;Q d5" (Ser#,e III)l!o$$o" x -%${A9 %$e'{S! y MDNC{S! y MDC{S!, y MC{S!,

x -p.6 w.1p2 y p.13v y 0.613 y 2.1v3

x -6. M%a *9 s$ ** 9## 4P* (-1v.w M%a) O$ f rng m?t c@t ng$"Vn liVn hWp th s` dKng thng x$"Vn cho t-nh toDn 0ng s$Ptdo tPt c; thFnh phZn t;i trIng. '$" nhiVn_ Mt Fi cX 5$an ch0c s` dKng th$c t-nhca m?t c@t ch$"Yn Oi trong t-nh toDn 0ng s$Pt do ho:t t;i. 'h$c t-nh m?t c@tch$"Yn Oi th Wc li,t kV phZn 2. 'rong - dK nF"_ th$c t-nh m?t c@t ng$"Vn thWc s` dKng cho t-nh toDn nF".#rder !o$$o" s$ress *der &res$ress#*9 a*d dead oad a$er ossesl

!o$$o" x -%${A9 %$e11{S! y MDNC{S! y MDC{S!,

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x -6.w66 y 11.p1v 1.111 0.3x -10.0 M%a b*9 s$ ** 9## 4P* d8# $Q, d*9 ,a d $=# d# 4P*

(-1v.w M%a) O*9 s$ ;q*4 d5" d8# $=# $rf*9 y (%S y D) sa "$ "Q$ b*9 s$l

$o& x -%${A9 y %$eC{S$ MDNC{S$ MDC{S$, M{S$,

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$ f rng 0ng s$Pt th Wc t-nh toDn khng =ao gm tE =iHn F co ngt. %X 5$anch0c nvng th khng kY Hn tE =iHn F co ngt trong thiHt kH thng thng nh@mmKc -ch gi;m 0ng s$Pt ko gi9i h:n ho?c cho 0ng s$Pt =ng khng i>$ ki,n c$icGng. 'E =iHn F co ngt Wc kY Hn th kHt 5$; thng thng cng thVm 0ng s$Ptko t:i D" Zm ca m?t c@t giBa nhp.b*9 s$ $P# ;Q sa "$ "Q$ d8# $Q, d*9 ,a dh b*9 h, $q*4 $=#l

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.{n +, ,8 ,-n ,8 878 n 2n &8 /78 63, 4, \ /`n 6%6n, ?6.NhBng m?t c@t Gng moment Jm c thY = n0t d9i tr:ng thDi gi9i h:n s` dKngng$"Vn do t;i trIng t\nh t;i liVn hWp F ho:t t;i. S/ n0t =@t Z$ trong =;n F khi (andas) t;i trIng gia tvng Ht n0t m rng x$ng dZm. tr- ca trKc tr$ng hLa cho mtm?t c@t c moment ngoFi ( ng$"Vn nhJn 0ng s$Pt nn t:i m?t dZm t:i tr- l/c cvng)th c thY xDc nh s` dKng phXng phDp th` i sai (trial and error approach)nh sa$*1. i; thiHt tr- ca trKc tr$ng hLa (Ass$me the location o the ne$tral axis.)

2. i; thiHt giD tr cho =iHn d:ng nn t:i t9 ch$ nn ngoFi cGng ( the extremecompression =er) D" ca dZm.'-nh toDn =iHn d:ng ko trong ct thp dIc ca =;nm?t cZ$ gi; thiHt =iHn d:ng th tha" Oi t$"Hn t-nh dIc theo chi>$ cao ca m?t c@t F=iHn d:ng =ng khng th gi; thiHt t:i tr- ca trKc tr$ng hLa.3. '-nh toDn 0ng s$Pt ko tXng 0ng trong ct thp =;n d/a trVn =iHn d:ng gi; nh.4. '-nh toDn l/c nn trong =V tng.&. uiYm tra s/ cZn =ng ca l/c trVn m?t c@t(d/ 0ng l/c_ l/c ko trong thp =;n Fl/c nn trong =V tng). 'ha" Oi gi; th$"Ht =iHn d:ng t:i D" ca dZm cho Hn khicJn =ng l/c th :t Wc.6. Sa$ khi l/c cJn =ng_kiYm tra cJn =ng moment ca m?t c@t (moment tE d 0ngl/c_moment ngo:i l/c F moment tE l/c nn F ko).

7. NH$ moment cJn =vng_ gi; thiHt tr- ca trKc tr$ng hLa F =iHn d:ng lF ng.NH$ moment th khng cJn =vng tha" Oi tr- gi; thiHt ca trKc tr$ng hLa F tiHptKc =9c 2 =Vn trVn.. Sa$ khi c; moment F l/c cZn =ng_ t-nh toDn giD tr 0ng s$Pt l9n nhPt trong =Vtng khi kHt 5$; giD tr =iHn d:ng l9n nhPt F mod$le ca =V tng tr:ng thDi Fnhi.$ f rng khi cng thVm l/c nn do ngo:i l/c tDc dKng | Wc trnh =F" Fo trong=V tng_ 0ng s$Pt t0c thi trong thp d 0ng l/c th gi;m =i h, sO mod$l$s WcnhJn Fo_ =i 0ng s$Pt nn thVm Fo x$ng 5$anh =V tng. S/ tha" Oi trong l/c ctthp d/ 0ng l/c th thng lF nh F Wc = 5$a trong t-nh toDn d9i J"./ d $/*4 $oQ* "$ "c$ ,t$ > W*9 "o"e*$ m" d8# $rP*9 $4Q# 9## 4P* s d*9.

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76/136

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77/136

. x 3.p6 X 106y (-p.661 X 106) y 1.wpv X 106 x -1.p0 X 10p

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x -v.610 X 10 N-"" 0 O

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78/136

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Sb, k4Q*9 , 4 s^ $ro*9 "c$ ,t$ @a ,Q*4 (Sp..3.2.2)

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i*4 *94a sh $4a ;j# $ro*9 ,B*9 $4b, $r* 9#Q $r ,a * ,4o / d *lA&s x d#* $/,4 $4& d.8. (""2) x 33 ""2

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d& x k4o=*9 ,Q,4 $ $4 ,4 ** *9o# ,W*9 ;:* $rf*9 $m" ,a ! $4&d.8. ("")

x 1vvv ""

As x d#* $/,4 $4& $48L*9 ,4 ko (""2) x 0.0 ""2

x 9## 4P* ,4= $^# $4#J @ ;*4 ,a $4& $48L*9 (M%a) x 20 M%a

ds x k4o=*9 ,Q,4 $/*4 $ $4 ,4 ** ;:* $rf*9 $m" ,a $4& $48L*9,4 ko ("")+ NA

As x d#* $/,4 $4& $48L*9 ,4 ** (""2) x 0.0 ""2

x 9## 4P* ,4= $^# $4#J @ ;*4 ,a $4& ,4 ** (M%a)+ NA

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80/136

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Mr x 1.0(1. X 1010) x 1. X 1010N-""Mo"e*$ 4 s^ * *4$ Q& d*9 ,4o $rP*9 $4Q# 9## 4P* ,8?*9 ; 1 v+p6 k-$ (Xe"!=*9 p.3-2)

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81/136

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Mr x 1. X 1010 N-""+ do \ ,= 4a# ;#V k4o=* $4[ $4a "* (!o$4&ro#s#o*s are O)

>..> VQ ,-0 n8 s> *4*9 $/*4 $oQ* s? !+ ,^$ $4& df, $P# ;q*4 ;Q ,a !=* "c$ ,5$4[ 9#= $4#:$ $4*4 }1w # k4o=*9 ,Q,4 10 "" $4a*4 }1w # k4o=*9 ,Q,42p0 "" (Xe" 4[*4 p.6-p).T/*4 $oQ* $j*9 d#* $/,4 $4& $r* ;?* !V r*9 ,a !=*l

As x A!ar{k4o=*9 ,Q,4 $4a*4 $4& (""2{"")C4o ,^$ $4& > ;q*4l As $o& x 2v{10 x 2.03 ""2{""C4o ,^$ $4& > ;Ql As !o$ x 2v{216 x 1.31 ""2{""Do ;+ As x 2.03 y 1.31 x 3.3 ""2{"".T/*4 $oQ* $rf*9 $m" ,a ,^$ $4& !=* $/*4 $ ;q*4 ,a !=*. *4*9 $/*4 $oQ* $4[ ;8


82/136

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, x As{0.vp1,! (Sp..3.1.1-+ "od#ed)Tro*9 ;l

As x d#* $/,4 ,a $4& $ro*9 ,4#V r*9 ,Q*4 4 4# 2v13 "" (""2)x As!sa! x (3.3)(2v13) x w3wp ""2

x 20 M%a, x 2 M%a1 x 0.p! x 1p "", x w3wp(20){~0.vp(0.p)(2)(1p) x 206 ""+

#Q $r , X& Xq !`*9 ,4#V d ,a !=* ,Q*4 ;Q d5" (20p "")+ do ;+ "c$ ,t$ $4[;8.>.!)Fnh ng cZn Wc nhn nhCn t:i tr:ng thDi gi9i h:n s` dKng lF n0t_ =iHn d:ng(deormations)_F 0ng s$Pt =V tng_ Wc ch\ ra trong mKc S&.7.3.4_ S&.7.3.6_ FS&..4. ng s$Pt n0t th Wc lP" khi mod$l$s phD ho:i S&.4.2.6.'hFnh phZn Wc cho lF t l, (&ro&or$#o*ed) b*9 s$ ko $ro*9 $4& $48L*9 >$rP*9 $4Q# 9## 4P* s d*9 k4B*9 ;8


83/136

.A x d#* $/,4 ,a ! $B*9 , ,W*9 $rf*9 $m" # $4& ,4 ,4 ko ;8# *48*9 !V "c$ ,a "c$ ,t$ *9a*9 "$ ;8L*9 $4*9 so*9 so*9 # $r,$r*9 4|a+ ,4#a ,4o s^ 8 &45* $r* $ro*9 / d * (&45* ). Tr, $r*9 4|a w ""$/*4 $ dQ ,a d5".*9 s$ * *4$ $ro*9 ,^$ $4& x 232.6 M%a 2p0 M%a O.

p.6.p.2 Mo"e*$ d8?*9 $P# "^# *^#Mt s cX 5$an ch0c nvng nhn nhCn tE =iHn F co ngt trong thiHt kH_ c kh; nvngmoment dXng sj phDt triYn t:i trK tr$ng gian d9i tDc dKng ca d..l_ t;i trIng dFi

h:n F tE =iHn co ngt. NhBng cX 5$an ch0c nvng nF" 5$" nh ct thp t:i D" cadZm t:i dZm ngang Y chng l:i moment dXng t-nh toDn t:i nhBng tr- nF".%ho nhBng cX 5$an ch0c nvng khng nhn nhCn tE =iHn F co ngt trong thiHt kH_khng ch@c moment dXng do tnh t;i t:i tr- trK sj khng Wt 5$D giD tr momentJm tE t;i trIng dFi h:n ca dZm liVn hWp t:i nhBng tr- nF". NhBng > x$Pt thkhng cZn thiHt cho moment dXng. '$" nhiVn_trong nhCn =iHt s/ hi,n di,n ;nhhng ca tE =iHn F co ngt_ hZ$ hiHt co 5$an ch0c nvng ch\ ra mt Fi ct thp Ychng l:i moment dXng.

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84/136

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1) nh &.6R& ch\ ra mt phXng Dn tha" thH lF "V$ cZ$ ko dFi mt Fi taothp t:i dZ$ c$i ca dZm Fo dZm ngang. # N8


85/136

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Hn >." # N8 ."] # D*6 n$n ,8 /Q ,-0 ,-2 (G8 8 &'n)

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86/136

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Hn >."e # D*6 n$n ,8 /Q ,-0 ,-2 (G8 &Qn)

>.. S 68 ,-%n , ,:; ..< (S>.>.5)MKc S&.&.3 ni rng (states that) s/ mi khng cZn kiYm tra (need not =e checked)khi giD tr 0ng s$Pt ko l9n nhPt trong =V tng d9i tr:ng thDi gi9i h:n s` dKng ### thWc lP" d/a theo gi9i h:n 0ng s$Pt ca =;ng S&..4.2.2R1. i9i h:n 0ng s$Pt trong=;ng nF" th Wc s` dKng trong - dK nF" F do _s/ mi ca ct thp d/ 0ng l/c

khng cZn thiHt kiYm tra.>..] ' /n (S>.].5.)Ui>$ kho;n S2.&.2.6 sj Wc nhn nhCn.'-nh toDn $n F ng sj nhn nhCn tnh t;i_ ho:t t;i_ d..l_ t;i trIng l@p d/ng_tE =iHn ca =V tng F co ngt_ F t/ trGng ct thp. UY xDc nh $n F ng_5$" nh ca i>$ S4.&.2.1_ S4.&.2.2_ F S&..&.& sj Wc Dp dKng.U $n t0c thi th Wc t-nh toDn s` dKng mod$l$s Fn hi cho =V tng nh ch\ ratrong i>$ S&.4.2.4 F lP" moment 5$Dn t-nh ng$"Vn_ #g_ theo i>$ S&.7.3.6.2. giD tr $n th Wc t-nh toDn d/a trVn d..l_ tnh t;i =;n thJn dZm_ =;n m?t cZ$_ Dnkh$n_ trIng lWng dZm ngangt F trIng lWng t-nh t;i thVm. iD tr ng thWc t-nh toDn d/a trVn ng =an Z$_ ng =an Z$ th Wc i>$ ch\nh cho tE

=iHn_ F ng c$i cGng. 'hng thng_ nhBng t-nh toDn nF" th Wc tiHn hFnh(cond$cted) =ng s` dKng chXng trnh mD" t-nh. %hi tiHt t-nh toDn th Wc trnh =F"nh sa$.i ^* do d.8. $b, $4L# $4[ ;8


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uf hi,$ dP$ Jm ch\ dn ng h9ng lVn.8hZn m>m t-nh toDn th thng s` dKngY xDc nh ng do m}i lo:i t;i trIng. t$" nhiVn_- dK t-nh toDn th Wc a ra h9ng dn nF".ue" !=*9 p.p-1 ,4o h, ,Z*9 d.8.N4" $ao $4& 1l 32 $ao $4& d/*4 k:$

h, ,Z*9 $b, $4L# x .112 X 106 N4o=*9 ,Q,4 $ ;Q ;5" ;:* $r, $r*9 4|a x w2 ""4o=*9 ,Q,4 $ ;Q ,a d5" ;:* $rf*9 $m" ,a *4" $ao $4& 1 x 13 ""i *9 do *4" $ao $4& 1l

%{S 1 x -(%$es2){(v,#I9)x -~.112 X 106(w2 13)(33 2232){~v(2w 03)(3.0p2 X 1011)

x -p0 "" (*9 *)N4" $ao $4& 2 l 6 $ao k4B*9 d/*4 k:$ $ 30v "" $/*4 $ d5 d5".

C4#V d# $rV* h, x 62 ""h, ,Z*9 $b, $4L# x .0w X 10p NT 4[*4 2-p a*d 2-6+ k4o=*9 ,Q,4 $ ;Q d5" ;:* $rf*9 $m" ,a *4" $4& 2

100 "".i *9 ,a *4" $ao $4& 2l%{S 2 x -%$es~2 ($ y 2X)2{(v,#I9)

x -.0wX10p(w2 100)~33 2232 ~62y2(30v)2{~v(2w 03)(3.0p2X1011)x -w.p "" (*9 *)

N4" $ao $4& 3l 6 $ao $4& k4B*9 d/*4 k:$ ,4#V d# 606 "" $/*4 $ ;5 d5".C4#V d# ,4J* $#:& x 62 ""h, ,Z*9 $b, $4L# x .0w X 10pNT 4[*4 2-p 4[*4 2-6+ k4o=*9 ,Q,4 $ ;Q d5" ;:* $rf*9 $m" ,a *4" $ao

$4:& s^ 3 100 "".i *9 do *4" $ao $4& 3l%{S 3 x -%$es~2 ($ y 2X)2{(v,#I9)

x -.0wX10p(w2 100)~33 2232 ~62 y 2(606)2{~v(2w 03)(3.0p2X1011)x -v.1 "" (*9 *)

Tj*9 ; *9 do dh b*9 h,l

%{S To$ x -p0 w.p v.1 x -6.6 "" (*9 *)$ f rng t-nh toDn cong (cam=er)_mt Fi cX 5$an ch0c nvng th gi; thiHt rngmt Fi d 0ng l/c th mPt mDt F ch\ s` dKng phZn trvm giD tr t-nh toDn =Vn trVn (-dK =ang 8enns"lania $ses ] ca giD tr trVn).'rong t-nh toDn theo sa$ dJ" giD trtoFn = th Wc s` dKng. Ngi s` dKng c thY kiYm tra l:i nhBng giD tr nF" Ygi;m theo "V$ cZ$ theo tiV$ ch$n ca ch Z$ t.S d*9 $4:$ d5" $4B*9 $48L*9 ;J XQ, ;*4 ; *9 ,a d5" 9#=* ;?* d8# $=#$rf*9 &4m* !^ ;V 4oc, $=# $rf*9 $\& $r*9 s d*9 $=# $rf*9 $/*4 $oQ* > ", p.2+

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x -.3 y 2v. y 2.3x -3.6 "" (*9 *)

i *9 * $4[ s d*9 ;J XQ, ;*4 ,ao ; ;Q k 9^#.

>..].! C8=+ a # ,4 ;5 $8. H[*4 p.6-w ,4o $4 sh &4Q,4fa V ,4#V d & ^$. C4#V d & ^$ $P# $r/ ,4J* $#:& $4[ $48L*9 $/*4$oQ* s d*9 &45* "V" # $/*4.

Hn >." # Hn 68n h$ 8=+ a ..].5 ' /n & &Qn ,| &' m?t F tr- n0t trong =V tng =;n m?t cZ$ F trong cZ$ kim lo:i cDi mF lFm "H$ ikh; nvng s` dKng F =>n. tE nvm 1]&_ s/ c g@ng Y trDnh i nhBng ;nh hngnF" =ng gi9i h:n t l, chi>$ cao F chi>$ dF" nhp ca giFn F dZm F =@t Z$ tEnhBng nvm 13]_ gi9i h:n ng do ho:t t;i th Wc m t; cho cng ch$ng mKc-ch. 'rong mt nghiVn c0$ gi9i h:n ng ca cZ$ AS%Q (1&)_ mt hi ngAS%Q_ tm ta nhBng thi>$ st trong cDch tiHp cCn tr$">n thng F nhBng l$ fuh;o sDt h:n chH do " =an tiHn hFnh khng c khng c =ng ch0ng thi,t h:i

nghiVm trIng kHt cP$ do d ng 5$D m0c. Mt Fi - dK kHt ni = h hng dZm cZ$thang_ sFn =V tng = n0t c thY c thY Wc s`a chBa c hi,$ 5$; hXn =ng cDchtha" Oi trong thiHt kH hXn lF so 9i i,c h:n chH h:n chH > ng.M?t khDc_ c; hai nghiVn c0$ lch s` F cDc kHt 5$; tE c$c kh;o sDt cho thP" r rFnglF ph;n 0ng tJm lf > ng cZ$ c thY lF s/ thng x$"Vn F 5$an trIng nhPt cami 5$an tJm > t-nh linh ho:t ca cZ$. '$" nhiVn_ nhBng ?c iYm ca cJ" cZ$ r$ngng Wc coi lF = ph;n i =i ngi i =_ hFnh khDch trong xe c thY cha WcxDc nh

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.uY tE _ khng c nghiVn c0$ sJ$ rng > ph;n 0ng ca con ngi Hn ch$"Ynng_ F hi,n na" ni ch$ng ng f rng "H$ t ch-nh ;nh hng Hn s/ nh:" c;mca con ngi lF kh; nvng tvng tc nh trDi ngWc 9i ng_ Cn tc_ Nh C"_ Hnthi iYm nF" trong lch s` khng c h9ng dn xDc nh Xn gi;n cho cDc gi9i h:nca ng tnh chPp nhCn Wc ho?c do d"namic motion. 'rong s tiV$ ch$n k{th$Ct hi,n hFnh_ l$Ct 'hiHt kH cZ$ ~ntario nvm 13 c 5$" nh toFn di,n nhPt liVn5$an Hn r$ng ng chPp nhCn Wc i 9i con ngi. %Dc tiV$ chng trong

S2.&.2.6.2 Wc coi lF tG" chIn. %h Z$ t c thY l/a chIn cDc tiV$ ch$n nF" nH$m$n. NH$ %h Z$ t l/a chIn Y gIi kiYm soDt ng_ cDc ng$"Vn t@c sa$ J" cthY Wc Dp dKng*

uhi i>$ tra ng ti a t$",t i_ tPt c; lFn thiHt kH ph;i Wc chPt t;i_ FtPt c; cDc thFnh phZn [ kV cZn Wc gi; nh nh nha$ Y lFm ng.

uhi kh;o sDt giD tr l9n nhPt ng c lCp_ tPt c; lFn thiHt kH nVn Wc chPtt;i_ F tPt c; phZn [ kV nVn gi; nh nh nha$ Y t:o ra ng.

%ho thiHt kH Zm liVn hWp_ m?t c@t thiHt kH nVn =ao gm => rng xe ch:" FphZn lan can liVn tKc_ li i =_ F mt phZn ca rFo c;n.

uhi kh;o sDt ch$"Yn tXng i_ s lWng F tr- ca t;i trIng lFn nVn l/achIn Y a ra hi,$ 0ng =Pt lWi nhPt_ tr- ca ho:t t;i F tO hWp t;i trIng s`dKng # ca =;ng S3.4.1R1 nVn Wc s` dKng_ =ao gm t;i trIng ng_ #M ho:tt;i nVn lP" tE S3.6.1.3.2_ cDc 5$" nh ca i>$ S3.6.1.1.2 nVn Dp dKng_

%ho cZ$ xiVn_mt m?t c@t ngang ng c thY Wc s` dKng cZ$ cong F xiVncong m?t c@t ngang h9ng tJm a right crossRsection )c thY Wc s` dKng. NH$ch s hB$ gIi cDc tG" chIn tiV$ ch$n t;i sng l,ch_ l,ch cZn Wc th/chi,n nh phZn l9n hXn ca.

a right crossRsection ma" =e $sed or c$red and c$red ske!ed =ridges aradial crossRsection ma" =e $sed. # the ~!ner inokes the optional lie loaddeection criteria_ the deection sho$ld =e taken as the larger o*

'hat res$lting rom the design tr$ck alone_ or 'hat res$lting rom 2& percent o

the design tr$ck taken together !ith the design lane load.T4eo ;#V S2.p.2.6.2+ 9## 4P* ; *9 do 4oP$ $=# {v00x 33 p2v{v00 x 1.w ""T/*4 $oQ* ; *9 4oP$ $=# XQ, ;*4 !`*9 &45* "V" "Q $/*4 v.2 "". v.2 1.wO

>.] T8, .e)'hiH kY kh; nvng ch$ l/c c@t theo tiV$ ch$n AAS'~R< th d/a trVn s/ =iHn Oica Gng nn . phXng phDp nF" kY Hn hi,$ 0ng ca l/c dIc trKc trong 0ng s` cal/c c@t ca m?t c@t Zm. gc ca l/c c@t _ _ F hng s l/c c@t _ hai ch0c nvng caDp dKng 0ng s$Pt c@t F =iHn d:ng dIc trKc ca m?t c@t.

H[*4 Sp.v.3..2-1 "#*4 4oP $4B*9 s^ h, ,t$.

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, x ,8L*9 ; ** ,a ! $B*9 !*9 x 2 M%a x 9## 4P* ,4= ,a ,^$ $4& *9a*9 x 20 M%a#= $4#:$ r`*9 $4a*4 }13 $4[ ;8.].!.9 4o=*9 ,Q,4 * *4$ ,4o ,^$ $4& *9a*9.

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.'hng s x th Wc o lng =iHn d:ng trong =V tng ca m?t ch$ ko. %ho nhBngm?t c@t ch0a -t nhPt ct thp ai tvng cng ti thiY$ Wc t-nh toDn trVn_ x c thYWc t-nh toDn s` dKng cng th0c sa$ J"*

NH$ giD tr x tE cng th0c S&..3.4.2R1 ho?c cng th0c S&..3.4.2R2 th Jm_ =iHn d:ngsj Wc lP"*

C4o / d $/*4 $oQ* *+ 9#Q $r $/*4 $oQ* ,a ,= h, df,+ N+ $4*4 &45* *9a*9,a dh b*9 h,+ &+ $4[ ;8$ S&..3.4.2_ po th nh ngha nh sa$*po + mt thng s Wc lP" nh lF mod$l Fn hi ca = thp 0ng s$Pt tr9c nhJn=i giD tr khD nha$ giBa =iHn d:ng giBa = thp cng cao F =V tng x$ng5$anh (ksi). %ho m0c thng thng ca d/ 0ng l/c_ giD tr ].7p$ sj th-ch hWp choc; cvng tr9c F cvng sa$.Ui 9i d/ 0ng l/c cvng tr9c_ nhJn mod$l$s Fn hi ca = thp =i s/ khDc nha$> =iHn d:ng giBa = thp d/ 0ng l/c F Gng =V tng x$ng 5$anh_ 0ng s$Pt trongnhBng tao thp khi =V tng O x$ng 5$anh chng lF 0ng s$Pt ca tao thp giaio:n t0c thi lc tr$">n l/c cvng. %ho thFnh phZn cvng tr9c_ mKc S%&..3.4.2 chophp po Wc lP" =ng 0ng s$Pt k-ch (zacking stress). iD tr nF" th thng l9n hXn].7p$.


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X x -0.000pp 0.0 NG+ do ; s d*9 ,B*9 $4b, @. Sp.v.3..2-3D#* $/,4 ,a ! $B*9 $ro*9 W*9 ko ,a d5" $4[ ;8


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, x 0.0v3(2.v)(6.v)(20p)(1v3p) x p.v0 X 10pN.T/*4 $oQ* sb, k4Q*9 ,t$ k4# , ,^$ $4& ;a#+ s.

s x ~Ad(,o$ y ,o$ )s#* {s (Sp.v.3.3-)#= $4:$ ,^$ $4& ;a# $4[ ;8# ,B*9 $4b, @. Sp.v.3.3-2 ;J *4`" oP#! :$ *b$ @Q "b,.

& x 0.0 ,4o $ao $4& dh b*9 h, $4*9.* x !`*9 s^ *4 4?* ,al, y s y & x p.v0 X 10p y 1.1p X 106 y 0.0 x 1.3p X 106N0.2p,!d y & x 0.2p(2)(20p)(1v3p) y 0.0 x 3.wp0 X 106N

Do ; + * x 1.3p X 106NH s^ sb, k4Q*9+ ,4o h, ,t$ > ! $B*9 $ $rf*9 $4B*9 $48L*9 (*or"a Ee#94$,o*,re$e)=0.w (Sp.p..2.1)Sb, k4Q*9 ,t$ , *4m* 4 s^+ rl

r x * (Sp.v.2.1-2)x 0.w(1.3p X 106) x 1.p62 X 106N h, ,t$ $/*4 $oQ* * *4$+ x

1.p1 X 106N O

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#J" $ra $r/ ,a "c$ ,t$ 9## 4P* ($4e ,r#$#,a se,$#o*) ,4o h, ,t$ $P# $r# 95* 9^#'heo i>$ S&..3.2_ ph;n l/c trong h9ng Dp dKng l/c gJ" ra l/c nn Fo phZndZ$ Zm_ tr- ca m?t c@t t9i h:n ca kiYm tra c@t sj Wc lP" s l9n ca ].&dcot ho?c d t-nh tE m?t trong ca D kV.Ui 9i cZ$ hi,n hB$_ => rng ca gi th Wc=iHt F kho;ng cDch th Wc o tE m?t trong ca gi. Ui 9i cZ$ m9i_ => rng cagi th thng khng =iH_t t:i tr- nF" mt trong hai cDch tiHp cCn sa$ th Wc s`dKng.

i; thiHt => rng ca gi d/a trVn kinh nghi,m 5$D kh0. Uo kho;ng cDch tE tJm ca gi. cDch tiHp cCn nF" th an toFn hXn cht.

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c@t. 8hJn t-ch cZ$ hi,n hB$ cDch tiHp cCn Z$ th thiH$ hKt s0c khDng c@t.

2) 'rong t-nh toDn kho;ng cDch tE trKc tr$ng hLa Hn th9 ch$ nn qc_ "H$ t sa$J" th cZn Wc nhn nhCn*

M?t ch$ nn t:i D" dZm. cng =V tng Wc s` dKng Y xDc nh qcca =V tng c sn

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., x 2 M%a, x w3wp(20){~0.vp(2)(0.p)(1p) x 206 "" ,4#V d ,a ,Q*4 d5" >

;Q (20p "")Do ;+ 9#= $4#:$ b*9 s ,a "c$ ,t$ 4[*4 ,4 *4\$ ;K*9.%h f rng nH$ giD tr qc th l9n hXn chi>$ dF" cDnh D" dZm_ 0ng s` hnh chBnhCt c thY Wc s` dKng sa$ khi hi,$ ch\nh chi>$ rng ca cDnh D" dZm kY Hni,n t-ch th/c ca dZm Gng nn. '$" nhiVn nH$c th/c s/ khng l9n hXn chi>$

dF" ca D" dZm_ ;nh hng Hn kHt 5$; th khng nhi>$ F i,c phJn t-ch c thYWc tiHp tKc mF khng cZn hi,$ ch\nh => rng ca D" dZm. f l$Cn nF" th Wc s`dKng trong - dK nF".C4#V ,ao ,a W*9 ,4 ** + a x 1, x 0.p(206) x 1pp ""4o=*9 ,Q,4 9#a h, ko h, ** do ^*l x de a{2 x 1w1 1pp{2 x 1v3 ""(1)

0.wde x 0.w(1w1) x 123 ""(2)

0.24 x 0.2(201p) x 1p1 "" (3)d x s^ * *4$ ,a (1)+ (2) a*d (3) x 1v3 ""8 r`*9 0.24 $4[ B* B* ! 4?* 4a# 9#Q $r k#a ,4o $$ ,= "c$ ,t$ $ro*9 d5".#Q $r * $4[ k4B*9 $r[*4 ! $ro*9 !=*9 p.-1 ;J r r*9.>.].5.5 {n +, 4, ,-%n @ ,_nT !=*9 p.3-+ b*9 s$ ,t$ $/*4 $oQ* $P# "c$ ,t$ *+ x 1.66 X 106N

x 0.w (s4ear) (Sp.p..2.1)! x !V r*9 !*9 ;5" x 20p ""

T ", Sp.v.2.w+ b*9 s$ ,t$ $ro*9 ! $B*9 l x ( &){(!d) x (1.66 X 106 0){~0.w(20p)(1v3) x p.0 M%a

H s^ Q& d*9 ,a b*9 s$ ,t$ $/*4 $o* ,4o ,8L*9 ; ** ,a ! $B*9l{, x p.0{2 x 0.1203 (4 s^ * k4B*9 $4a ;j# $ / d $4eo ;?* A*4)+ p.0{2

k4B*9 !`*9 0.1203. *4*9 $/*4 $oQ* $4eo sa sg s d*9 s^ 0.1203)>.].5.9 C, ,:; n$n ,8 ,8Z+4o=*9 ,Q,4 * *4$ ,4o $4a*4 $4& ;a# }13 # 4a# *4Q*4 $4[ ;8 !8,p..2.2.

s wv3 ""4o=*9 ,Q,4 * *4$ ,4o ,^$ $4& *9a*94o=*9 ,Q,4 * *4$ ,a $4& *9a*9 $4[ ;8


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.Ui 9i m?t c@t Gng moment Jm_ t-nh toDn x_ s` dKng cng th0c Q5. S&..3.4.2R1F gi; thiHt khng c ct thp d/ 0ng l/c.

C4o / d *+ 9#Q $r ,a ,= h, df, $/*4 $oQ* + N+ $4*4 &45* ;b*9 ,a dh b*9

h,+ &+ $4[ ;8$ dFi phDt triYn (deelopmentlength) =Vn ngoFi m?t c@t xem xt. NH$ m?t c@t ?t =Vn trong chi>$ dFi phDt triYn(deelopment length) ca mt Fi thanh_ nhBng thanh nF" c thY = 5$a ho?c l/ctrong nhBng thanh nF" Wc t-nh theo t l, ca h, s giBa chi>$ dFi phDt triYn toFn= F mt phZn. cng nVn xem xt hi,$ ch\nh tr- tJm ca ct thp Y l/c nh hXntrong nhng thanh thp mF c chi>$ dFi phDt triYn khng Z" .

d x 1v3 ""s x 2.0 X 10p M%a&s x 1.w6p X 10pM%aA&s x d#* $/,4 ,a $4& dh b*9 h, > "c$ ,4 ko x 0.0 ""2

T4a $4: ,Q, !#:* * $ro*9 ,B*9 $4b, @. Sp.v.3..2-1 ;J XQ, ;*4 XlX x ~2.0v1X10w{1v3 y 0.p(1.66X106 0),o$ 3p 0{~2(2.0X10p)(w3wp) y 0 x 0.00062

(#Q $r * ;8


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.N# s 9#a 9#Q $r $ro*9 4*9 # 9#Q $r 95* # 9#Q $r $/*4 $oQ* {, x 0.1203+ *#s 4*9 # {, 0.1 0.12p. Sa ; *# s 9#a 9#Q $r $ro*9 ,$ 95* # 9#Q $r $/*4 $oQ**4$ X x 0.00062+ ; *# s 9#a ,$ # X 0.000p ,$ X 0.000p. '=*9d8# ;m $4[ ,4o $4 &45* #* @a* ,a !=*9 Sp.v.3..2-1 # 9#Q $r *9* 9^, 9#Q $r *# s. $B "L B , ,Q, 9#Q $r *# s.

T-0 ,| @n S>.e.5.9.!"1

T !=*9 $r*l x 32. de9rees x 2.36

8 r`*9 9#Q $r *# s k4B*9 k4Q, !#$ ;Q*9 kJ so # 9#Q $r $/*4 $oQ* " k4B*9,5* *# s. %4m* $/,4 sa ;m $4[ dha $r* 9#Q $r *# s ;J ,*9 ,& ,4o *98L# sd*9 "$ $# # $4a" k4=o ,4o ,Q,4 $4b *.#J" $ra 9#Q $r C4o ", ;/*4 $/*4 $oQ* X+ 9#Q $r $4[ ;8


105/136

.A x 2(;#* $/,4 $4a*4 }13) x 2(12w) x 2pv ""2

s x 1v "" x w0 de9reess x 2pv(20)(1v3)(,o$ 32.wv){1v x 1.23 X 106 NSb, k4Q*9 ,t$ da*4 ;*4+ *+ $4[ ;8$S&.1].1].1t:i tr:ng thDi gi9i h:n s` dKng.

8r + sAs (S&.1].1].1R1)'rong *

s + 0ng s$Pt trong ct thp khng Wc Wt 5$D 14] M8aAs + tOng thp theo phXng 0ng = tr- kho;ng cDch h4 t-nh tE Z$ dZm

(mm2)h + chi>$ cao toFn = (oerall depth) ca cP$ ki,n c sn (mm)

S0c khDng khng Wc nh hXn 4 d/ 0ng l/c khi tr$">n l/c cvng.T $4#:$ k: > !8, p..lh, ,Z*9 K, $rV* $P# ;5 d5" x 32(wv.1)(1301) x .10w X 106 NuQ, ;*4 ,^$ $4& ,5 ;J ;P$ $# sb, k4Q*9 $^# $4#J ,5 s d*9 9#Q $r **4$ s x 10 M%a ("aX).Do ;+ 0.0(.10w X 106) x 10(As)

As x 11 ""2

T d#* $/,4 "$ ;a# ,4b U 4a# *4Q*4 2pv ""2+ XQ, ;*4 s^ ;a# ,5* $4#:$.11{2pv x .pp s d*9 p ;a#.

N4*9 ;a# ,4 U * &4=# ;c$ $ro*9 k4o=*9 4{ $/*4 $ ;5 d5".4{ x 1v2p{ x p6 ""

S d*9 p ;a# ,4 U # k4o=*9 ,Q,4 p "" *48 ,4q ra $ro*9 4[*4 p.-1.>.].> C, ,:; @^ 8 (C%nn6n, -8n%-6n,) (S>.1J.1J.!)%ho kho;ng cDch 1.&d 1.&(12&) + 273 mm t-nh tE Z$ dZm_tvng cng ct thpsj Wc ?t Y h:n chH thp d/ 0ng l/c =;n cDnh d9i. ct thp "V$ cZ$ th Li hikhng Wc = hXn thanh No. 3_ oi!s kho;ng cDch khng Wt 5$D 1&] mm F hnhd:ng th =ao =Ic nhng tao thp. Uai chB "V$ cZ$ Y chng l:i l/c c@t F Y tham|n giD tri l9n nhJt ca ai ch0 "V$ cZ$ Wc ch\ ra trong =;ng &.7R1 cho cDc m?tc@t khDc nha$. kho;ng cDch l9n nhPt "V$ cZ$ Wc ch\ ra trong =;ng &.7R1 Gng

10p


106/136

.Z$ dZm th l9n hXn 1&]mm. %ho Zm tPt c; tao thp Wc ?t cDnh d9i_ haicDch tiHp cCn c thY s` dKng Y cho ra ct thp = giB "V$ cZ$*

1) i;m kho;ng cDch thp ai ch0 Gng Z$ dZm (1.&d) khng Wc 5$D1&] mm

2) U?t thp 0ng ch-nh ca thp ai ch0 9i kho;ng cDch "V$ cZ$ ca phJnt-ch c@t theo phXng 0ng. chi tiHt thp d0ng D" dZm Y =ao lP" thp d/ 0ng l/c_nhBng thp nF" 9i kho;ng cDch th khng l9n hXn 1&] mm =Vn trong Z$ dZm. ct

thp ai ch0 F ct thp = giB trong cDch tiHp cCn nF" sj khng cGng kho;ngcDch F i,c O =V tng th c thY kh khvn.Ui 9i Zm c mt Fi tao thp d?t trong =Kng Zm_ cDch tiHp cCn (1) nVn Wc s`dKng.Tro*9 / d *+ ,Q,4 $#:& ,\* 1 $4[ ;8


107/136

.

10


108/136

.

Hn >.]"! # M3, 4, A"A ,| n >.]"1 C4, n$n $ *6 *n &*+ &*6>.]. L ,-%n , ,:; h @$% 6 8b+ n $ .e.5.>)'hVm Fo moment Dp dKng_ M$_ hi,$ 0ng l/c sa$ J" ng gp cho l/c trong ctthp theo phXng dIc* /c c@t_ $

'hFnh phZn 0ng ca d/ 0ng l/c /c dIc_ N$ S0c khDng c@t =i ct thp ngang_ sUY t-nh toDn hi,$ 0ng l/c nF" trong Fo l/c gia c theo chi>$ dIc_i>$ S&..3.& "V$cZ$ ct thp dIc Wc cJn i m}i m?t c@t_ kh; nvng ch$ ko ca ct thp m?tch$ ko khi $n_ th l9n hXn ho?c =ng l/c ' Wc t-nh toDn*

'rong *s +s0c khDng c@t c$ng cPp =i ct thp ngang t:i m?t c@t xem xt Wc cho =i

cng th0c S&..3.3R4_ ngo:i trE s cZn l9n hXn $ (N) + gc nghiVng ca 0ng s$Pt nn cho Wc s` dKng Y xDc nh s0c khDng c@tdanh nh ca m?t c@t xem xt_ Wc xDc nh =ng 5$i nh S&..3.4 (deg) + h, s s0c khDng Wc lP" theo S&.&.4.2 th-ch hWp cho moment_ l/c c@t F s0ckhDng dIc.

10v


109/136

.#J" $ra * $4[ ,5 ,4o "c$ ,t$ ;c$ $P# $r/ k4B*9 ! 4?* k4o=*9 ,Q,4 !`*90.pd,o$ $ 9^#. #Q $r ,4o "c$ ,t$ $# 4P* ,4o ,t$ > $r/ 95* 9^# 0.pd,o$ ; ;8


110/136

.4 x h, ,t$ *9a*9 $r* "$ ;?* ,4#V d# ,a d5" (N) x h, ,t$ $/*4 $oQ* (N) x 1.02 X 106N (ue" !=*9 p.-2)de x k4o=*9 ,Q,4 9#a $rf*9 $m" ,a $4& > W*9 ,4 ko ,a ;5" ;:* $m*

,a W*9 ** > !=* "c$ ,5 ("") x 1vvp "" (ue" !=*9 p.-2)4 x 1.02 X 106{1vvp x N{""

4o=*9 ,Q,4 $4& ;a# ,4b U $P# $r/ * x p ""

#= $4#:$ r`*9 ;a# ;8 ;#V Sp.v..2%, x h, ** $48L*9 X* B*9 9, # "c$ &4*9 ,t$ (N)

T/*4 $oQ* sb, k4Q*9 ,t$ da*4 ;*4 $r* "$ ;?* ,4#V d# d5".#= $4#:$ !V "c$ > ;q*4 ,a d5" $4[ sP,4 , $Po *4Q" (#*$e*$#o*a ro94e*ed)

, x 0. M%a a*d x 1.0 (Sp.v..2)' @a h, ** $r* !V "c$l %, x 0.0A, x 106p ""2{""A x 1.1 ""2{"" x 20 M%a

Do ;* x 0.(106p) y 1.0~1.1(20) y 0.0 x 122 N{""

110


111/136

.T4eo ;#V Sp.v..1+ sb, k4Q*9 ,t$ da*4 ;*4+ *+ s d*9 $ro*9 $4#:$ k: &4=# $4a"*l

* 0.2,A, (Sp.v..1-2)Hoc, * p.pA, (Sp.v..1-3)

Tro*9 ;l, x 2v M%a ,8L*9 ; ,a ! $B*9 : 4?* (M%a) ,4o ! $B*9 ,a !=* "c$ ,5* 0.2 ,A, x 0.2(2v)(106p) x pw6 N{""

Hoc, * p.pA, x p.p(106p) x pvpv N{""Do ; + * ;8.5)Sh d,4 ,4J* do @Q $r[*4 $4# ,B*9 Xm t&'rong trng hWp th/c tH_ giai o:n thi cng nVn tr ho|n i,c xJ" d/ng m F trK mFnm trong ho?c li>n k> 9i tr- @p Pt_ Hn khi Pt Wc @p F Zm ch?t. $ ch\nh k-ch th9c th-ch 0ng kHt 5$; s/ dch ch$"Yn

c thY x;" ra ca m F trK tE s/ lFm ch?t Pt sa$ khi chng Wc xJ" d/ng.%los$re po$rs c thY Wc s` dKng Y lFm nh i hi,$ 0ng ca 0ng s$Pt tr9c =aogm s/ co ng@n => rng =t k-n (!idth o seals) F k-ch c[ ca gi.

3 ,0n (S19..!)i Wc chIn cho mt 0ng dKng cK thY ph;i c t;i trIng phG hWp F kh; nvng dich$"Yn. b;ng S14.6.2R1 c thY Wc s` dKng nh lF mt h9ng dn khi so sDnh s/khDc nha$ ca cDc h, thng gi.

H8b+ n ,8 ,-hn , g+ ,| % nn 3n 8 +aZn ,8 8 (S19..5)/c ngFm x$Pt hi,n khi =Pt k phZn nFo dch ch$"Yn = c;n tr. /c do t;i trIng tDcdKng tr/c tiHp th =ao gm tnh t;i ca cZ$ F t;i trIng xe c_ ng Pt_ n9c F t;itrIng gi. i,c Dp dKng cho tEng tr:ng thDi gi9i h:n th ph;i Wc nhCn =iHt.i th thng Wc ?t mt di,n t-ch mF tr- th$ thCp mt s lWng l9n chPt=n (dirt)_ m_F thc " cDc Pn > > vn mLn F s/ phong ha. F kHt 5$;_ gith nVn Wc thiHt kH F chH t:o Y c kh; nvng =;o , chng l:i tDc ng mitrng F cho php d dFng Fo Y kiYm tra.

111


112/136

.T}n g+$n /= 8 &n 8 (E$ dF" l9p Fn hi F h, s hnhd:ng ca gi. U mi_ =>n_ s/ tDch l9p_ ch;" F [ ca ct thp_ c0ng ca l9pFn hi F h:n chH hnh hIc ph;i Wc tha m|n.

Pn ;; ,8, ai phXng phDp thiHt kH th Wc cho php =i tiV$ ch$n AAS'~R$ S14.7.6_ th Dp dKng cho gi phng_ ct thp giacng F gi gia cng sWi th" tinh cng nh lF cotton d$ck pads.

8hXng phDp b_ ch\ ra i>$ S14.7.&_ th Dp dKng cho gi Fn hi c gia cngct thp. 8hZn sa$ J" F - dK sa$ th d/a trVn phXng phDp b. $ chothiHt kH gi phZn 3 s` dKng c; hai phXng phDp A F phXng phDp b.

T+' ,0n +n $ /c,


113/136

.%Pp ca Ct li,$ Fn hi th Wc l/a chIn trVn cX s Gng nhi,t ca tr- cZ$ F=i =;ng S14.7.&.2R2. Gng nhi,t Wc ch\ ra trong nh 6R1.

Bn S19.].>.!"! # /`n n8b, &' ,; / ; ,; n, $ /c, n lVn lVn nh ch\ ra i>$ S14.6.3.12) Dc nh r Ct li,$ Fn hi 9i m0c giD tr nhi,t nh nhPt cho i,c s` dKng. uhii>$ kho;n 5$" nh ca l/c ?c =i,t Wc kHt hWp trong thiHt kH nhng khng c$ngcPp ma sDt trWt => m?t thPp (lo! riction sliding s$race)_ trong trng hWp cZ$sj Wc thiHt kH Y ch$ Wc gPp i l/c c@t ch\ ra i>$ S14.6.3.1.3) Dc nh Ct li,$ Fn hi 9i m0c nhi,t thPp cho i,c s` dKng khi i>$ kho;n5$" nh l/c ?c =i,t th Wc kHt hWp trong thiHt kH nhng khng Wc c$ng cPp

113


114/136

.mt => m?t trWt ma sDt thPp_ trong trng hWp thFnh phZn ca cZ$ sj Wc thiHtkH Y ch$ Wc =n lZn t;i trIng chit ta i>$ S14.6.3.1.

.1 T8, 6', 8 &n 8 8$ n , ,:; % *6 ,-%n ,8 /Q ,-0 ,-2.

Ct li,$ Fn hi thng dKng 9i c0ng 6] thang o Shore A $ S14.7.&.3.2_hi,$ 0ng ca l/c x$ng k-ch lVn gi Fn hi c thY Wc = 5$a. Ng$"Vn nhJn cai>$ nF" lF hi,$ 0ng ca l/c x$ng k-ch th gZn nh nh trong tOng t;i trIng F =i gi9i h:n 0ng s$Pt th d/a trVn tDc ng ca mi (atig$e)_ nhBng gi9i h:n nF" thkhng d dFng xDc nh. %ho - dK nF"_ l/c x$ng k-ch (33 giD tr l9n nhPt ca ph;nl/c do xe t;i )cng thVm Fo 6 2&& N F 1.6&x1]&N cho l/c c@t ngFm t-nh toDn(actored end shear) tr:ng thDi gi9i h:n s` dKng F tr:ng thDi gi9i h:n cng

tXng 0ng. N lF nhBng l/c nh_ do C"_ s/ =ao hFm hi,$ 0ng t;i trIng ng th aHn mt thiHt kH an toFn hXn mt cht (slightl"). 8h;n l/c ca ho:t t;i trVn gi th Wc lP" =ng giD tr l/c c@t ngFm do ho:t t;i l9nnhPt ( lie load end shear). NhCn thP" rng i 9i dZm Wc ni liVn tKc cho ho:tt;i_ c hai hFng gi trVn trK. Mt 5$" trnh khDc c thY chPp nhCn Wc lF chia giD trl9n nhPt do ph;n l/c ca ho:t t;i trVn trK =ng nha$ giBa hai hFng gi. Ui>$ nF" sja Hn kHt 5$; t;i trIng lVn gi thPp so 9i i,c s` dKng l/c c@t ngFm ca dZm(end shear) cho thiHt kH gi. %Dch tiHp cZn nF" th khng Wc lP" trong - dK nF"_ dnhiVn lF_ l/c c@t ngFm trong dZm th Wc Dp dKng cho t-nh toDn gi (rather_ thegirder end shear !as applied to the =earing).

.1.1 X &Qn 8bn ,0 8 n n,.

^# $P# $r/ $r $4[ ,^ ;*4 k4B*9 ! !#:* dP*9 $r8


115/136

. x b*9 s$ ** $r*9 ![*4 do 4oP$ $=# (M%a) x Mod ,t$ ,a \$ # ;* 4# (M%a)S x 4 s^ 4[*4 dP*9 ,a & d *4$ ,a 9^#.

iJ $4a "* 9## 4P* 12.0 M%a+ d#* $/,4 *4 *4$ ,a 9^#+ Are@+ ** $4a "* ,5l

Are@ 1.2w2X106{12.0 x 1.0 X 10p""2

, ,a !=* ,Q*4 ;Q ,a d5" $4[ $48L*9 Q$ 9,. ^# $4[ ** 4& 4?* "$ ,4K$ so

# "c$ &4*9 ,a "c$ !/,4 *9oP# $r "$ $" ,b*9 ;8 ,P*4) k/,4 $48, df, 1w0 "" ;J ;=" !=o r`*9 9## 4P* b*9s$ ** * *4$ $4[ ;8


116/136

.N4*9 ;#V k4o=* * 9## 4P* b*9 s$ ,t$ !#:* dP*9 $ro*9 & ;* 4#. M^#@a* 4 9#a b*9 s$ ,t$ h, ** &4 $4, $rh, $#:& $4eo 4 s^ 4[*4 dP*9+ #4 s^ 4[*4 dP*9 * 4?* $4[ d* ;:* k4= *Z*9 ,4 $=# $rf*9 ,ao 4?* .i5 $#*+ 9#=# ra 4 s^ 4[*4 dP*9 d8# $j*9 $=# $rf*9+ ST+ !`*9 ,Q,4 #:$ P# ,B*9 $4b,@. S1..p.3.2-3 ,4o 9^# ,^ ;*4 ,4^*9 P# !#:* dP*9 ,t$.

ST s{2.00 (S1..p.3.2-3)Tro*9 ;l

s x %T{Are@%T x %4=* h, * *4$ d8# $j*9 $=# $rf*9 (N) x 1.2w2 X 106Ns x 1.2w2 X 106{~1w0(61p) x 11.1 M%a x 1.0 M%aST 11.1{~2.00(1.0)

p.pp (1)#=# ra ;8


117/136

.biHn d:ng ca gi cao s$ do tOng t;i trIng F do ho:t t;i sj Wc nhn nhCn mtcDch riVng =i,t.biHn d:ng t0c thi th Wc lP"*

+ ihri (S14.7.&.3.3R1)'rong *

i + =iHn d:ng nn trong l9p cao s$ th0 ith ca gi nhi>$ l9n.hri + chi>$ dF" ca l9p th0 ith trong gi nhi>$ l9p (in.)

iD tr i th Wc xDc nh tE kHt 5$; th- nghi,m ho?c =ng phJn t-ch khi xem xtch$"Yn dFi h:n. i,$ 0ng tE =iHn ca gi th Wc thVm Fo trong =iHn d:ng t0cthi. hi,$ 0ng tE =iHn nVn Wc xDc nh tE thng tin th-ch hWp cho gi Fn hi kHthWp Wc s` dKng. 'rong trng hWp khng c dB li,$ > Ct li,$ th-ch hWp_ giD trWc a ra mKc S14.7.&.2 c thY Wc s` dKng.

.1.!.5 B8n n 4, (S1..p.3.)

Ui>$ 5$" inh nF" cZn Wc kiYm tra nH$ gi lF gi di ng.NH$ gi Wc xem xt lFgi c nh_ i>$ kho;n nF" th khng Wc Dp dKng. %h th-ch ca i>$ kho;n nF"th Wc c$ng cPp nh sa$_ nhng khng c thiHt kH kiYm tra nFo Wc thY hi,n.

ch$"Yn l9n nhPt theo phXng ngang ca cP$ trc thWng tZng_ o

_ th Wc lP" lFch$"Yn c/c h:n ng$"Vn nhJn =i tE =iHn F co ngt F kHt hWp ca d/ 0ng l/c_ cogi|n nhi,t . biHn d:ng c@t l9n nhPt ca gi t:i tr:ng thDi gi9i h:n s` dKng_ s_ thWc lP" o_Wc s` Oi t-nh Fo c0ng cP$ trc h: tZng F 5$" trnh thi cng. NH$=> m?t c ma sDt trWt thPp Wc s` dKng _ s khng Wc lP" l9n hXn =iHn d:ngtXng 0ng cho s/ trWt Z$.i th "V$ cZ$ tha m|n*

hrt 2 s (S14.7.&.3.4R1)'rong *hrt + tOng chi>$ dF" l9p Fn hi (tOng chi>$ dF" ca tPt c; l9p Fn hi) (mm)s+ biHn d:ng c@t l9n nhPt ca Ct li,$ Fn hi d9i tr:ng thDi gi9i h:n s` dKng(mm)i9i h:n nF" trong hrt =;o ;m rng rolloer t:i c:nh F s/ tDch l9p do mi th khngWc x;" ra. em S%14.7.&.3.4 cho "V$ cZ$ nghiVm ng?t hXn i 9i =iHn d:ng trWtdo ch$ k t;i cao nh lF l/c h|m xe F r$ng..1.!.9 T} ; n:n / %$a(S1..p.3.p)'r:ng thDi gi9i h:n s` dKng th Wc Dp dKng. 'hiHt kH xoa" th Wc lP" lF tOng giDtr l9n nhPt ca hi,$ 0ng s/ @ng m?t t0c thi ca ng song song giBa D" cadZm F \nh dZm F 5$a" Z$ dZm do t;i trIng tDc dKng F s/ di ch$"Yn.MKc -ch ca nhBng "V$ cZ$ sa$ Y =;o , i,c nhO =Ct ca =Pt k gc nFo ca gid9i =Pt k tO hWp nFo ca t;i trIng F s/ 5$a" tng 0ng.

^# ,4 *4\$ $4[ 9#= $4#:$ $4a "* ,5 *4j !\$ * (sa$#s $ re@#re"e*$s)*: ,4K*9 $4a "* ,Q, ,5 sals 1.0S(s{*)('{4r#)2 (S1..p.3.p-1)Tro*9 ;l* x s^ 8


118/136

.4a# ,4#V d ,a & !* $ro*9+ $4B*9 s^+ *+ , $4: 9#a $Z*9 $4" "$ *a ,4o "7#& !* *9o#.

4r# x 12. ""s x b*9 s$ ** * *4$ $ro*9 9^# (M%a)x 11.1 M%a' x C4#V d# ,a $5" *: sh @a V $r, *9a*9 4oc, !V r*9 ,a $" *: #,Xoa * $4[ $4eo ,4#V df, ,5 ("")

x 1w0 ""s x 9, @a $^# ;a do $j*9 $=# $rf*9 (rads)C4o / d *+ s sg !ao 9" 9, @a do 4oP$ $=# $=# $rf*9 $4# ,B*9 (8 ,8, -$). :$ @= ,a ; *9 d8# $Q, d*9 ,a d8 b*9 h, $=# $rf*9 d# 4P*+D5" b*9 s$ $r8, $4B*9 $48L*9 , 9, @a d8# $=# $rf*9 d# 4P* $4[ *98 ' }n &Qn $ 8 &n 8 (S1..p.3.6)

^# $4[ ;8 $rP*9 $4Q# 9## 4P* s d*9 ,4q ra $ro*9!=*9 S3..1-1.^# $4[ $4a "* ,B*9 $4b, @. S1..p.3.6-1 $4[ ;8


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.

E4erel x 1w0 "" x 61p ""

4r$ x $j*9 ,4#V d ,a & ,ao s ("") x 2(6) y 2(12.) x 3 ""C4o 9^# 4[*4 ,4 *4\$ k4# $4[ * 4?* + ; j* ;*4 sg ;8# sh 4oQ*;j# 9#Q $r $ro*9 ,B*9 $4b, @s. S

comprehensive design example

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