8/11/2019 Tacoma Narrows Bridge Collapseg dfg dfgdfg dfg dgdf gdfgdf gdfg dg g g dfgfd

1/2

Md. Mahbub Uzzaman ID: 2006-3-80-016

Sec: 01 Sub: EEE 404

Tacoma Narrows Bridge Collapse

The oriina! Tacoma "arro#$ %ride #a$ o&ened 'o 'ra((ic on )u!* 1+ 1,40. I' #a$!oca'ed in a$hin'on S'a'e+ near ue' Sound.

The Tacoma "arro#$ %ride #a$ 'he 'hird-!one$' $u$&en$ion bride in 'he Uni'ed S'a'e$

a' 'he 'ime+ #i'h a !en'h o( /,3, (ee' inc!udin a&&roache$. I'$ '#o $u&&or'in 'o#er$#ere 42/ (ee' hih. The 'o#er$ #ere 2800 (ee' a&ar'.

n!* 'hree mon'h$ a('er 'he Tacoma "arro#$ bride o&ened in 1,40+ 'ie-do#n cab!e$in'ended 'o $'i((en 'he bride $na&&ed durin a #ind$'orm. The cab!e$ had been anchored

in'o 'he round and a''ached 'o 'he &ar'$ o( 'he bride dec 'ha' #ere moin 'he mo$'.

The cab!e$ #ere re&!aced. The bride became no'oriou$ (or !are moemen'$ durin hih

#ind$. n "oember 1,40+ #i'h a #ind e!oci'* o( abou' 60 &h+ 'he bride bean

'#i$'in and o$ci!!a'in io!en'!*. The bride #a$ '#i$'in abou' 4/ deree$ in '#o#ae$+ and o$ci!!a'in u& and do#n one me'er in nine #ae$. The o$ci!!a'ion$ reached 8

me'er$ a$ 'he bride 'ore i'$e!( a&ar' 5e* and Sa!adori+ 1,,2+ e!d and 7ar&er+ 1,,.The ma'hema'ic$ ino!ed in 'he o$ci!!a'ion$o( a $!ender bride are di((icu!'+ and #ere

no' #e!! under$'ood in 1,40. 9o#eer+ $u$&en$ion bride$ had (ai!ed in 'he 18'hand 1,'h

cen'urie$. The Tacoma "arro#$ bride #a$ 'hree 'ime$ more (!eib!e 'han 'he ;o!den;a'e or ;eore a$hin'on bride$. 5ie 'he %ron-hi'e$'one %ride+ i' u$ed a

dam&er+ bu' 'he dam&er (ai!ed a!mo$' immedia'e!*. The o'her bride$ had a much rea'er

$'i((ne$$ and ma$$ momen' o( iner'ia+ and #ere !e$$ &rone 'o #ind-induced acce!era'ion$

5e* and Sa!adori+ 1,,2. The re&!acemen' bride+ #hich i$ $'i!! in u$e+ had (our !ane$ra'her 'han '#o and 10 m dee& $'i((enin 'ru$$e$ in &!ace o( 'he oriina! 2.4 m 'ru$$e$

e!d and 7ar&er+ 1,,. The re$i$'ance 'o 'he er'ica! o$ci!!a'ion i$ &ro&or'iona! 'o 'hema$$ o( 'he bride+ #hich i$ doub!ed in 'he re&!acemen' de$in.Shou!d more a''en'ion hae been &aid 'o 'he cau$e$ o( 'he 'ie-do#n cab!e (ai!ure< I$ 'he

occa$iona! (ai!ure o( a round-breain $'ruc'ure &ar' o( 'he co$' o( doin bu$ine$$

Causes of Failure:

The edera! or$ =enc* = ine$'ia'ed 'he co!!a&$e o( 'he Tacoma "arro#$%ride and (ound 'he (o!!o#in:

The bride #a$ #e!! de$ined and #e!! bui!'. hi!e i' cou!d $a(e!* re$i$' a!! $'a'ic

(orce$+ 'he #ind cau$ed e'reme undu!a'ion$ #hich cau$ed 'he bride>$ (ai!ure.

"o one rea!ized 'ha' Tacoma>$ ece&'iona! (!eibi!i'* cou&!ed #i'h i'$ inabi!i'* 'oab$orb d*namic (orce$ #ou!d mae 'he #i!d o$ci!!a'ion$ #hich de$'ro*ed i' &o$$ib!e.

?er'ica! o$ci!!a'ion$ #ere cau$ed b* 'he (orce o( 'he #ind and cau$ed no $'ruc'ura!

damae.The (ai!ure o( cab!e band on 'he nor'h end+ #hich #a$ connec'ed 'o 'he cen'er 'ie$+

&robab!* $'ar'ed 'he '#i$'in mo'ion o( 'he bride. The '#i$'in mo'ion cau$ed hih

$'re$$e$ 'hrouhou' 'he bride+ #hich !ead 'o 'he (ai!ure o( 'he $u$&ender$ and co!!a&$eo( 'he main $&an.

8/11/2019 Tacoma Narrows Bridge Collapseg dfg dfgdfg dfg dgdf gdfgdf gdfg dg g g dfgfd

2/2

Md. Mahbub Uzzaman ID: 2006-3-80-016

Sec: 01 Sub: EEE 404

= $u$&en$ion bride #a$ 'he mo$' &rac'ica! choice (or 'he $i'e.

The $u&eri$ion o( and #orman$hi& on 'he bride #a$ ece&'iona!.@iidi'* aain$' $'a'ic (orce$ and riidi'* aain$' d*namic (orce$ canno' be de'ermined

u$in 'he $ame me'hod$.

E((or'$ #ere made 'o con'ro! 'he am&!i'ude o( 'he bride>$ o$ci!!a'ion.Sub$eAuen' $'udie$ and e&erimen'$ are needed 'o de'ermine 'he aerod*namic (orce$

#hich ac' on $u$&en$ion bride$.

Technical Concerns:

The Tacoma "arro#$ %ride co!!a&$e $ho#ed enineer$ and 'he #or!d 'he im&or'anceo( dam&enin+ er'ica! riidi'*+ and 'or$iona! re$i$'ance in a!! $u$&en$ion bride$ @o$$+

1,84. nce 'he 'hrea' o( '#i$'in #a$ rea!ized 'here are man* #a*$ 'ha' 'he di$a$'er o(

Tacoma "arro#$ cou!d hae been aer'ed. Main an* one o( 'he (o!!o#in adBu$'men'$

cou!d hae &reen'ed 'he co!!a&$e:U$e o&en $'i((enin 'ru$$e$ #hich #ou!d a!!o# 'he #ind (ree &a$$ae 'hrouh 'he

brideIncrea$e 'he #id'h 'o $&an ra'io

Increa$e 'he #eih' o( 'he bride

Dam&en 'he brideU$e an un'uned d*namic dam&er 'o !imi' 'he mo'ion$ o( 'he bride

Increa$e 'he $'i((ne$$ and de&'h o( 'he 'ru$$e$ or irder$

S'ream!ine 'he dec o( 'he bride 5e* and Sa!adori+ 1,,2

Ethical Concerns:

In 'he (ace o( ne# 'echno!o*+ ho# do #e ba!ance &ub!ic #e!(are and &rore$$< I(Moi$$ei(( had de$ined a bride $imi!ar 'o 'he one$ #hich had a!read* &roen 'heir

$'abi!i'*+ Tacoma "arro#$ %ride #ou!d neer hae co!!a&$ed co$'in 'hou$and$ o(

do!!ar$ and endanerin man* !ie$. I' #ou!d a!$o hae been $ini(ican'!* moree&en$ie. n 'he o'her hand+ i( enineer$ had neer 'ried innoa'ie 'echniAue$+

$u$&en$ion bride$ ma* neer hae been bui!' a' a!!. =' 'he 'ime o( 'heir in'roduc'ion+ no

one be!ieed 'ha' a $u$&en$ion bride cou!d $a(e!* accommoda'e 'rain$. @oeb!in+

ho#eer+ 'oo a amb!e+ &u$hed 'he !imi'$ o( 'he curren' 'echno!o*+ and bui!' a$u$&en$ion bride 'ha' he be!ieed cou!d $a(e!* $u&&or' rai! 'ra((ic. 5uci!* he #a$

correc'+ and $u$&en$ion bride$ $oon became #ide!* acce&'ed e'ro$i+ 1,8/. Moi$$ei((

a!$o 'oo a amb!e+ 'r*in 'o crea'e a !oner+ $!eeer+ !e$$ e&en$ie bride+ b* &u$hin'he !imi'$ o( 'echno!o*. 9e+ ho#eer+ #a$ no' a$ !uc*+ and #ha' cou!d hae been a

brea'hrouh in 'echno!o* 'urned in'o a ca'a$'ro&hic (ai!ure. Eer* 'ime enineer$ &u$h

'he !imi'$ o( 'echno!o* 'he* ri$ a $imi!ar !o$$+ $ome'ime$ een a !o$$ o( !i(e. 9o# muchi$ 'oo much< hen i$ a &o$$ib!e adance #or'h a ri$ 'o &ub!ic $a(e'*< ha' can 'he

enineerin &ro(e$$ion do 'o mae 'he im&!emen'a'ion o( ne# 'echno!o* $a(er< Do our

curren' &eer reie# and bui!din code commi''ee &roce$$e$ adeAua'e!* &ro'ec' &ub!ic

$a(e'*