137695864 Pre Stressed Concrete Structures

7/25/2019 137695864 Pre Stressed Concrete Structures

1/42

PRESTRESSEDPRESTRESSED

CONCRETECONCRETE

STRUCTURESSTRUCTURES

BY,BY,

A.DINESHA.DINESH

ROLL NO:137R5A0101ROLL NO:137R5A0101

CMRTC.CMRTC.

Department ! C"#"$ En%"neer"n%Department ! C"#"$ En%"neer"n%


2/42

CONTENTSCONTENTS

IntroductionIntroduction

How to make prestressed concreteHow to make prestressed concrete

AdvantagesAdvantages

Difference between RCC !SCDifference between RCC !SC

!SC in Construction Industr"!SC in Construction Industr"


3/42

INTRODUCTION-INTRODUCTION-

A Brief HistoryA Brief History

E&%ene 're())"net *1+7-1/ e#te m&2 ! ")E&%ene 're())"net *1+7-1/ e#te m&2 ! ")

$"!e t te re)ear2 e#e$pment an 2n)tr&2t"n !$"!e t te re)ear2 e#e$pment an 2n)tr&2t"n !

pre)tre))e 2n2rete )tr&2t&re) an ") r"%t$( namepre)tre))e 2n2rete )tr&2t&re) an ") r"%t$( name

4te !ater ! pre)tre))e 2n2rete. It ") tr&% ")4te !ater ! pre)tre))e 2n2rete. It ") tr&% ")

e"2ate re)ear2 tat man( ! te te2n"6&e) ane"2ate re)ear2 tat man( ! te te2n"6&e) an

pra2t"2e) &)e ta( t &"$ )pe2ta2&$ar anpra2t"2e) &)e ta( t &"$ )pe2ta2&$ar an

ae)tet"2 )tr&2t&re) are p))"$e.ae)tet"2 )tr&2t&re) are p))"$e.

're())"net a2"e#e te 8r)t )&22e)) 9"t pre)tre))e're())"net a2"e#e te 8r)t )&22e)) 9"t pre)tre))e

2n2rete "n mar"ne 2n)tr&2t"n, a#"n% )e2&re te2n2rete "n mar"ne 2n)tr&2t"n, a#"n% )e2&re te

tener t 2rre2t te treatene !&nat"n) ! tetener t 2rre2t te treatene !&nat"n) ! te

LeHar#e mar"ne term"na$ &)"n% pre)tre)) te2n"6&e).LeHar#e mar"ne term"na$ &)"n% pre)tre)) te2n"6&e).

TheThe

beginningbeginning

E&%ene !re())"net*1+7-1/E&%ene !re())"net*1+7-1/


4/42

PrecastPrecast

pretensionepretensione

ho!!o" for#eho!!o" for#e

s!abss!abs re)tre))e 2n2rete ") &)e ta( !rre)tre))e 2n2rete ") &)e ta( !r$ar%e &"$"n% 9r;) "n man( 2"#"$$ar%e &"$"n% 9r;) "n man( 2"#"$en%"neer"n% 8e$) )&2 a)en%"neer"n% 8e$) )&2 a)....

Ra)Ra) B&"$"n%)B&"$"n%) Br"%e)Br"%e)


5/42

INTROD#CTIONINTROD#CTION

contd$contd$

A prestressed concrete member is one in w%ic% t%ere %aveA prestressed concrete member is one in w%ic% t%ere %ave

been introduced interna& stresses of suc% a magnitude' and a&sobeen introduced interna& stresses of suc% a magnitude' and a&so

distribution' t%at t%e stresses resu&ting from e(terna& &oading aredistribution' t%at t%e stresses resu&ting from e(terna& &oading are

counteracted to a desired degree)counteracted to a desired degree)

*H+ !RESTRESS ,*H+ !RESTRESS ,

!restressing app&ies an initia& compressive a(ia& force to t%e!restressing app&ies an initia& compressive a(ia& force to t%e

concrete w%ic% great&" reduces or e&iminates t%e interna&concrete w%ic% great&" reduces or e&iminates t%e interna&

stresses)stresses)

It does t%is app&"ing a tensi&e stress to a stee& cab&e runningIt does t%is app&"ing a tensi&e stress to a stee& cab&e running

t%roug% t%e concrete) T%e stee& cab&e is t%en anc%ored and t%et%roug% t%e concrete) T%e stee& cab&e is t%en anc%ored and t%e

compressive force is t%en transferred to t%e concrete b" t%ecompressive force is t%en transferred to t%e concrete b" t%e

bond forces$bond forces$


6/42

Te ene8t) ! pre)tre))"n% are :-Te ene8t) ! pre)tre))"n% are :-1.1. Cra2;"n% ") %reat$( re&2e r e$"m"nate, anCra2;"n% ") %reat$( re&2e r e$"m"nate, an

/./. App$("n% te pre)tre))"n% !r2e e$9 teApp$("n% te pre)tre))"n% !r2e e$9 te

ne&tra$ a=") "n&2e) te mment) 9"2 pp)ene&tra$ a=") "n&2e) te mment) 9"2 pp)e

t)e 2a&)e ( te e=terna$$( app$"e $a),t)e 2a&)e ( te e=terna$$( app$"e $a),t&) )"%n"82ant$( re&2"n% e>e2t"n.t&) )"%n"82ant$( re&2"n% e>e2t"n.

3.3. Memer )e2t"n) are )ma$$er tan re"n!r2eMemer )e2t"n) are )ma$$er tan re"n!r2e

2n2rete )e2t"n) !r te )ame "mp)e $a)..2n2rete )e2t"n) !r te )ame "mp)e $a)..


7/42

Base on the #etho of app!yingBase on the #etho of app!yingprestress to the concrete #e#ber, theprestress to the concrete #e#ber, the

Prestressing can be c!assie as.-Prestressing can be c!assie as.-

PRE-TENSIONIN/ 0ETHOD +PRE-TENSIONIN/ 0ETHOD +

POST-TENSIONIN/ 0ETHOD+POST-TENSIONIN/ 0ETHOD+


8/42

PRE-TENSIONIN/PRE-TENSIONIN/

re ten)"n"n% ") ne met ! app$("n% pre)tre)),t&) ?re ten)"n"n% ") ne met ! app$("n% pre)tre)),t&) ?

Tenn) e"ter pa)) tr&% a )"n%$e m&$ r a $"ne ! m&$)Tenn) e"ter pa)) tr&% a )"n%$e m&$ r a $"ne ! m&$)!r m&$t"p$e memer) arran%e en t en an 2an e atta2e!r m&$t"p$e memer) arran%e en t en an 2an e atta2eat ne en t 8=e an2ra%e.at ne en t 8=e an2ra%e.

Te tenn) are ten ten)"ne !rm te 8=e an2ra%eTe tenn) are ten ten)"ne !rm te 8=e an2ra%eet9een an e=terna$ "nepenent an2ra%e t %"#e teet9een an e=terna$ "nepenent an2ra%e t %"#e tere6&"re ten)"$e !r2e "n te tenn.re6&"re ten)"$e !r2e "n te tenn.

Te tenn) are ten e$ "n p$a2e 9"$e te 2n2rete ") p&re.Te tenn) are ten e$ "n p$a2e 9"$e te 2n2rete ") p&re.


9/42

Te tenn) are ten 8na$$( tr"mme @ a)Te tenn) are ten 8na$$( tr"mme @ a)

)9n e$9)9n e$9..


10/42

POST-TENSIONIN/POST-TENSIONIN/

)t-Ten)"n"n% ") anter met ! app$("n% pre)tre)) t a 2n2rete)t-Ten)"n"n% ") anter met ! app$("n% pre)tre)) t a 2n2retememer, t&)-memer, t&)-

Te tenn ") p$a2e "n te 2rre2t p)"t"n "n te !rm9r;Te tenn ") p$a2e "n te 2rre2t p)"t"n "n te !rm9r;9"t te ea-en an2ra%e an $"#e en an2ra%e, tr&%9"t te ea-en an2ra%e an $"#e en an2ra%e, tr&%9"2 te tenn pa))e).9"2 te tenn pa))e).

Te 2n2rete ") ten p&re an $e!t t aren.Te 2n2rete ") ten p&re an $e!t t aren.


11/42

Dea-enDea-enanchorageanchorage

T pre#ent te tennT pre#ent te tenn!rm )$"pp"n% a2; "t ")!rm )$"pp"n% a2; "t ")$2;e "nt te$2;e "nt te

an2ra%e ( mean) !an2ra%e ( mean) !a )p$"t 9e%e $2ate "na )p$"t 9e%e $2ate "nte arre$ ! tete arre$ ! tere2e))e an2ra%e.re2e))e an2ra%e.


12/42

Tenn) &)e !r pre)tre))"n% %enera$$(Tenn) &)e !r pre)tre))"n% %enera$$(2n)")t) ! )e#era$ "% )tren%t )tee$ 9"re) !2n)")t) ! )e#era$ "% )tren%t )tee$ 9"re) !)ma$$ "ameter 9rappe ar&n a )"m"$ar 9"re.)ma$$ "ameter 9rappe ar&n a )"m"$ar 9"re.


13/42

T%is is ca&&ed aT%is is ca&&ed aprestressingprestressingstrand -strand -Tendons) .adeTendons) .ade

of %ig% strengt%of %ig% strengt%stee&' it wi&&stee&' it wi&&

soon besoon be

embedded inembedded in

concrete)concrete)


14/42

Ba)e n 9 te tenn) are &)e ,te( 2an eBa)e n 9 te tenn) are &)e ,te( 2an e2$a))"8e a)2$a))"8e a)

1.1. Bne tenn)Bne tenn)/./. nne tenn).nne tenn).

Bne tenn) 2an a$) e &)e. Te pr2e)) ")Bne tenn) 2an a$) e &)e. Te pr2e)) ")

e))ent"a$$( te )ame e=2ept tat te pre)tre))"n%e))ent"a$$( te )ame e=2ept tat te pre)tre))"n%!r2e ") tran)!erre t te 2n2rete t ( rea2t"n)!r2e ") tran)!erre t te 2n2rete t ( rea2t"n)at te an2ra%e) an ( te n )tre))e) et9eenat te an2ra%e) an ( te n )tre))e) et9eente 2n2rete an te ne tenn.te 2n2rete an te ne tenn.

nne tenn) are nrma$$( a))em$e &nernne tenn) are nrma$$( a))em$e &ner!a2tr( 2n"t"n). Te( 2n)")t) ! )tran) r!a2tr( 2n"t"n). Te( 2n)")t) ! )tran) r9"re) tat are 9rappe r en2a)e "n p$a)t"2 a#"n%9"re) tat are 9rappe r en2a)e "n p$a)t"2 a#"n%een 8r)t 2ate 9"t %rea)e r a "t&m"n&)een 8r)t 2ate 9"t %rea)e r a "t&m"n&)mater"a$.mater"a$.


15/42

In t") >rIn t") >r

2n)tr&2t"n2n)tr&2t"n

ne tenn)ne tenn)

are pr#"e "n teare pr#"e "n teeam) an teeam) an te

&nne tenn)&nne tenn)

"n te r") ! te"n te r") ! te

tr&% )$a.tr&% )$a.

BONDEDBONDED

UNBONDEDUNBONDED


16/42

Te pt%rapTe pt%rap

)9) te)9) te

tenn $a(&t !rtenn $a(&t !r

a p)t-ten)"nea p)t-ten)"ne

>at )$a.>at )$a.

Te tenn) are p$a2e "n p)"t"n e!re te 2n2rete ")Te tenn) are p$a2e "n p)"t"n e!re te 2n2rete ")

p&re.


17/42


18/42


19/42

How !restressed concrete is madeHow !restressed concrete is made

It a&& begins at t%e prestressed concrete p&ant)


20/42

T%e prestressingT%e prestressing

strand is stretc%edstrand is stretc%ed

across t%e castingacross t%e casting

bed)bed)


21/42

An2ra%e) emee "n te 2n2rete memer are %enera$$(An2ra%e) emee "n te 2n2rete memer are %enera$$(

re6&"re n$( !r p)t ten)"n"n%. re ten)"ne memer) arere6&"re n$( !r p)t ten)"n"n%. re ten)"ne memer) are

man&!a2t&re an are an2re ( n )tre))e) rater tanman&!a2t&re an are an2re ( n )tre))e) rater tan

an2ra%e).an2ra%e).

One an2ra%e )"mp$( $) te en ! te tenn "n p)"t"n ,One an2ra%e )"mp$( $) te en ! te tenn "n p)"t"n ,9"$e te ter ") &)e 9"t te a2; t )tre)) te tenn. Ea29"$e te ter ") &)e 9"t te a2; t )tre)) te tenn. Ea2

an2ra%e ") atta2e t te en ! te tenn e!re tean2ra%e ") atta2e t te en ! te tenn e!re te

2n2rete ") p&re .Te t(pe ! an2ra%e &)e epen) n te2n2rete ") p&re .Te t(pe ! an2ra%e &)e epen) n te

n&mer ! tenn) an 9eter te( are )tran) r 9"re).n&mer ! tenn) an 9eter te( are )tran) r 9"re).


22/42

A pre)tre))"n% a2; ")A pre)tre))"n% a2; ")atta2e t te &t)"eatta2e t te &t)"ep$ate ! te an2ra%ep$ate ! te an2ra%e

tr&% 9"2 te en)tr&% 9"2 te en)! te tenn) pre2t.! te tenn) pre2t.On2e te a2; a) eenOn2e te a2; a) een2nne2te t te2nne2te t tetenn), )tre))"n% 2antenn), )tre))"n% 2ane%"n. Tee%"n. Tepreeterm"nepreeterm"ne)tre))"n% !r2e 2an e)tre))"n% !r2e 2an eapp$"e t ea2 tennapp$"e t ea2 tenn

"n"#"&a$$(. Te !r2e ")"n"#"&a$$(. Te !r2e ")app$"e a22r"n% t teapp$"e a22r"n% t tee)"%n en%"neer)e)"%n en%"neer))pe2"82at"n).)pe2"82at"n).


23/42


24/42

Specia& trucks bringSpecia& trucks bringt%e concrete to t%et%e concrete to t%ecasting bed w%erecasting bed w%ere

t%e pouring begins)t%e pouring begins)


25/42

Once t%eOnce t%e

pouring ispouring is

comp&ete' acomp&ete' atarp is p&acedtarp is p&acedover t%e formover t%e formand app&ied toand app&ied to

cure t%ecure t%e

cementcement


26/42

T%e prestressing strandsT%e prestressing strandsare cut and t%e concreteare cut and t%e concreteform is removed from t%eform is removed from t%e

casting bed)casting bed)


27/42

T%e ends areT%e ends are

c&eaned and t%ec&eaned and t%e

prestressingprestressingstrands are sea&edstrands are sea&edwit% a protectivewit% a protectivecoatingcoating


28/42

T%e end/productT%e end/productis s%ipped to ais s%ipped to a

bui&ding site)bui&ding site)


29/42

Bon StressesBon Stresses Te pre)tre)) !r2e "n a ne tenn ")Te pre)tre)) !r2e "n a ne tenn ")

tran)!erre t te 2n2rete ( n )tre))e).tran)!erre t te 2n2rete ( n )tre))e). Tere are t9 )ta%e) at 9"2 n )tre))e) areTere are t9 )ta%e) at 9"2 n )tre))e) are

2n)"ere "n te e)"%n ! pre)tre))e 2n2rete2n)"ere "n te e)"%n ! pre)tre))e 2n2rete

e$ement).e$ement).

At Tran)!er,At Tran)!er, te tenn) ! a preeterm"nete tenn) ! a preeterm"ne

e$ement are re$ea)e, an te pre)tre)) !r2e ")e$ement are re$ea)e, an te pre)tre)) !r2e ")

tran)!erre t te 2n2rete ( n )tre))e).tran)!erre t te 2n2rete ( n )tre))e).

'$e=&ra$ n )tre))e)'$e=&ra$ n )tre))e)e#e$p 9en memer) aree#e$p 9en memer) are)&e2te t e=terna$ $a"n%. H9e#er ,)&2)&e2te t e=terna$ $a"n%. H9e#er ,)&2

)tre))e) are $";e$( t e ne%$"%"$e &nt"$ te)tre))e) are $";e$( t e ne%$"%"$e &nt"$ te

memer a) e#e$pe >e=&ra$ 2ra2;).memer a) e#e$pe >e=&ra$ 2ra2;).


30/42

AD0ANTA1ESAD0ANTA1ES

Improved resistance to s%earing forcesImproved resistance to s%earing forces

Reduce t%e s%ear forces deve&oped at t%e supportReduce t%e s%ear forces deve&oped at t%e support

sectionssections

StifferStiffer

Indirect &ong term savings is more)Indirect &ong term savings is more)

Econom" for &ong span structuresEconom" for &ong span structures


31/42

CO.!ARISON 2ET*EEN RCC !SCCO.!ARISON 2ET*EEN RCC !SC

Tensi&e Strengt%Tensi&e Strengt%

StiffnessStiffness

S%earS%ear

Cracking def&ectionCracking def&ection

Serviceabi&it"Serviceabi&it"

Econom"Econom"

Safet"Safet"


32/42

!restressed concrete in construction!restressed concrete in construction

industr"industr"

It is we&& estab&is%ed fact t%at t%e basic econom" ofIt is we&& estab&is%ed fact t%at t%e basic econom" ofprestressed concrete &ies in its %ig% strengt% to weig%tprestressed concrete &ies in its %ig% strengt% to weig%tand strengt% to cost ratios ' its resistance to fire and strengt% to cost ratios ' its resistance to fire corrosion' its versati&it" and adaptabi&it")corrosion' its versati&it" and adaptabi&it")

It is idea&&" suited forIt is idea&&" suited for

3ong span 2ridges3ong span 2ridges

.u&tistor" bui&dings/4&at s&abs.u&tistor" bui&dings/4&at s&abs


33/42


34/42


35/42


36/42

Hig%wa" 56 2ridge over Osage River in .issouri 3and Crossing /

*est Span and Abutment


37/42


38/42

T%e 4&at S&ab f&ooring

s"stem incorporates

prestressed concreteunits designed for eas"

and fast p&acement

w%i&e re7uiring t%e

minimum on site work

to obtain a finis%ed

f&oor and cei&ing)


39/42

T%e &arge component

units are craned into

position' providing an

immediate working

p&atform w%ic%' wit% t%eaddition of an in situ

concrete topping' gives a

suspended f&oor wit% a

f&at' stee& formed soffit)

Temporar" propping isre7uired for &onger

spans)


40/42


41/42

S%##aryS%##ary

H9 t ea$ 9"t te $9 ten)"$e )tren%t ! 2n2rete (H9 t ea$ 9"t te $9 ten)"$e )tren%t ! 2n2rete (

pre)tre))"n% te memer.pre)tre))"n% te memer. Te me2an"2) ! te pre)tre))"n% )()tem &)"n% a r9 !Te me2an"2) ! te pre)tre))"n% )()tem &)"n% a r9 !

;) a) e=amp$e.;) a) e=amp$e.

H9 te pre)tre))"n% !r2e ") app$"e t a memer at )"te.H9 te pre)tre))"n% !r2e ") app$"e t a memer at )"te.

A r"e! ")tr( ! te e#e$pment ! pre)tre))"n% !rm "t)A r"e! ")tr( ! te e#e$pment ! pre)tre))"n% !rm "t)

"n#entr E&%ene 're())"net &p t te mern a(."n#entr E&%ene 're())"net &p t te mern a(.

Te met) ! pre)tre))"n%-Te met) ! pre)tre))"n%-

re ten)"ne pre)tre))"n%,re ten)"ne pre)tre))"n%,

)t ten)"ne re)tre))"n%,)t ten)"ne re)tre))"n%,

Bne an &nne tenn),Bne an &nne tenn), An2ra%e),An2ra%e),

Bn )tre))e).Bn )tre))e).


42/42

THANK YOUTHANK YOU

Documents

137695864 Pre Stressed Concrete Structures