KUIS 2.docx

7/24/2019 KUIS 2.docx

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SI-3112 STRUKTUR BETON

KUIS 2

Dosen: Prof. Ir. Bambang Budono! ".E.! P#.D

Dsusun o$e# :

N%"% : %$fredo Bas&an 'erema

7/24/2019 KUIS 2.docx


SOAL NO 1

b 3)) mmd /)) mm

# /() mm

f 0 2.( "Paf /)) "Pa

%s / D-22 1(21!1/3 mm2

Tentukan As(bal), As(max), As(min), dan Check Creeping!

AA"AN NO 1#enentukan As(bal)

STEP 1 : S%R%T ρ ba$ dan PER4ITUN5%N β1

7/24/2019 KUIS 2.docx


ab= β1

× cb=0,85×240=204

STEP 3 : "ENENTUK%N %s7ba$8 D%RI PERS%"%%N KESETI"B%N5%N

9 T 0,85× f c' × b × ab= As (bal)× f y

A s ( bal )=0,85× f c

' × b × ab

f y =0,85×27,5×300×204

400 =3576,375mm2

#enentukan As(max)

STEP 1 : S%R%T ρ ba$ dan PER4ITUN5%N β

ρ ba$ ε0 )!))3 6 εs ε

ε y=0,004

Sara& ma*smum sesua SNI 2/-2)13

β1=0,85

STEP 2 : "ENENTUK%N 0 b D%RI PERS%"%%N SE5ITI5% KESEB%N5UN%N

0,003cmax

= ε y

d−cmax

0 003d 0 003×400

7/24/2019 KUIS 2.docx


As ( min )=

√ f c '

4 f y× b × d= √ 27,5

4 ×400×300×400=393,303mm

2

As ( min )=

1,4

f y× b × d=

1,4

400×300×400=420mm

2

Dar +er#&ungan da&as! d0ar n$a %s7mn8 ang +a$ng ma*smum. D+$#$a# n$a %s7mn8 ada$a#

/2) mm2

STEP 2 : "ENENTUK%N NI%I amn

amin= A

s (min ) × f y

0.85× f c' ×b

= 420×400

0,85×27,5×300=23,957mm

2

Check Creeping

STEP 1 : "ENENTUK%N NI%I "n D%RI D%T% %s7mn8

Mn=T (d−0,5a )= As (min ) × f y × ( d−0,5a )=420×400× (400−0,5×23,957 )=65,188 Knm

∅=0,9

STEP 2 : "ENENTUK%N NI%I "0r

Mcr=0,62√ f c ' ×b × h

2

6=0,62√ 27,5×

300×4502

6=32,929 kN m

STEP 3 : 9REEP 94E9K

7/24/2019 KUIS 2.docx


SOAL NO $

b 3)) mmd /)) mm

d< () mm

f 0 2.( "Paf /)) "Pa%s7a&as8 2 D-1= /)2.2> mm2

%s7ba?a#8 / D-22 1(21 1/3 mm2

7/24/2019 KUIS 2.docx


Cs= A s (atas )'

× f ' s= A s ( atas )

' × ε

' s× ES

ε' s=(

c−d'

c )× ε y=(c−50

c )×0.003

Cs=402,29×( c−50

c )×0.003×200000 AA..718

Cc=0,85×27,5×0,85c ×300 AA..728

Ts= As × f y=1521,143×400=608457,2 AA..738

STEP 3 : PERS%"%%N 9S! 99! D%N TS

9S @ 99 Ts

402,29×( c−50

c )×0.003×200000+0,85×27,5×0,85c ×300=608457,2

STEP / : ITER%SI NI%I 9

Sara& &eras ang d$a*u*an ada$a# sebaga ber*u&

• f '

s≤ f y

• ga$a& 2C

• Cs+CcTs

I&eras +er&ama 701))8

( )

7/24/2019 KUIS 2.docx


!alat =643733,583−608212,34

643733,583×100=5,58 >2 7Tda* "emenu#8

f '

s=90−50

90×0,003×200000=266,667<400( f y )

Karena ga$a& &da* memenu#! ma*a #arus d$a*u*an &eras $eb# $an;u&

I&eras *e&ga 70(8

402,29×( 85−50

85 )×0.003×200000+0,85×27,5×0,85×85×300=608457,2

=)=)/2!/2 =)212!3/ 7"emenu#8

!alat =606042,42−608212,34

606042,42×100=0.35 >2 7"emenu#8

f '

s=85−50

85×0,003×200000=247,059<400 ( f y )

5a$a& memenu#! ma*a n$a 0(

STEP ( : "EN9%RI NI%I "n

a= β1

× c=0,85×85=72.25

M n=C '

c (d−a

2 )+C '

s ( d−d' )

M n=402,29×( 85−50

85 )×0.003×200000×(400−72,25

2 )+0,85×27,5×0,85×85×300× (400−50)

M 213 494kN

7/24/2019 KUIS 2.docx


SOAL NO %

b ()) mm

d =)) mmd< () mm

f 0 3) "Paf /)) "Pa

%s / D-22 1(21!1/3 mm2

Tentukan apakah bal&k memenuhi s'arat As(max) dan As(min)!

AA"AN NO %

STEP 1: U%S SE5ITI5% %9 D%N PERS%"%%N KESETI"B%N5%N

A 0 5× b × 0 5× 500

× × 5

×2 ∑ H 0 T 99

7/24/2019 KUIS 2.docx


β1=0.85−0.05×( f c

' −28

7 )=0.85−0.05×( 30−28

7 )=0,836

c=249,075

0,836=297,937mm

STEP 3 : 94E9K B%OK D%%" KE%D%%N UNDER REINFORCED 7UR8

ε y=f y

E s

= 400

200,000=0.002

ε s=d−c

c × εc=

600−297,937

297,397×0.003=3.047×10

−3

ε y<εs

Ba$o* da$am *eadaan under reinforced

STEP / : "EN9%RI NI%I %s7maF8

cmaks= 0.003

0.003+ε s

× d= 0.003

0.003+0.004×600=257.14mm

amaks= β1

× cmaks=0.84×257.14=216mm

A s ( maks ) × f y=0.85× f c' × A c

As ( maks)=

0.85× f c' × A c

f y=

0.85× f c' × 5

13× a

2

f y

7/24/2019 KUIS 2.docx



1)2=!> mm2

STEP = : 9REEP 94E9K

9ree+ 9#e0* d+er$u*an *arena %s G /H3 %s7mn8

M n=T ×(d−2

3×amin)=C c ×(d−

2

3×a)=0.85× f c

' × 5

13×a

2×(d−

2

3×a)

M n=0.85×30× 5

13×249,075

2×(600−2

3×249.075)=264,038 kNm

M cr=f cr × $ = M cr=0.62×√ f c' ×

136

b h3

1

3h

=0.62×√ f c' b h

2

12

M cr=0.62×√ 30×500×650

2

12=59,782 kNm

∅ M n ≥ 43

M cr

4

7/24/2019 KUIS 2.docx


SOAL NO

# =)) mm

b /)) mm

d (() mm

d1< () mmd2< 1)) mm

d2< 1)) mm

7/24/2019 KUIS 2.docx


STEP 2 : PERS%"%%N KESETI"B%N5%N UNTUK "ENENTUK%N 9S1! 9S2! TS3! 6 TS/

∑ H =0 99@9S1@9S2TS3@TS/

C c=0.85× f c' × β1× c × b

C s1= A s1 × f s1' =603,429×

c−50

c ×0.003×200,000

C s2= A s2 × f s2' =402,286× c−100c

×0.003×200,000

T s3= A s3 × f s3' =760,572×

500−c

c ×0.003×200,000

T s4= A s4 × f s4' =1521,143×

550−c

c ×0.003×200,000

Karena f0< 2 "Pa!

β1=0.85−0.05×( f c

' −28

7 )=0.85−0.05×( 30−28

7 )=0,836

STEP 3 : ITER%SI NI%I 9I&eras d$a*u*an dengan &ra$ and error. Karena arab$e ang dseda*an 0u*u+ bana*! ma*a

dguna*an &ab$e un&u* mem+ermuda#. Sara& &eras &ersebu& ada$a#

7/24/2019 KUIS 2.docx


ε s4=d−c

c ×ε c=

550−80

80×0.003=17.625×10

−3

ε s4 ≥ εs (max )

STEP ( : "EN9%RI NI%I %s7mn8

%da 2 rumus d SNI 2))2-2)13 &ersebu& ang menen&u*an n$a %s7mn8

As ( min )=

√ f c '

4 f y× b × d= √ 30

4 ×400×400×550=753.119mm

2

As ( min )=

1,4

f y× b × d=

1,4

400×400×550=770mm

2


) mm2

STEP = : 9REEP 94E9K

9ree+ 0#e0* d+er$u*an ;*a

%s 7&er+asang8 G /H3 %s 7mnma$8

Karena ada ang memenu# sara& da&as! ma*a +er$u d$a*u*an ana$ss

∅ M n ≥ 4

3 M cr

7/24/2019 KUIS 2.docx


M cr=0.62×√ 30×1

6×400×600

2=81,5 kNm

∅ M n ≥ 4

3 M cr

0.9×420,271≥ 4

3×81.50

7/24/2019 KUIS 2.docx


378,2439≥108.67#t&r&n(hi Tabe$ I&eras N$a 9

c εs1 εs2 εs3 Cc Cs1 Cs2 C Ts3 Ts4 T Galat

50 0 -0.003 0.027 426360 0 0 426360 304228.8 608457.2 912686 114.06464

60 0.0005 -0.002 0.022 511632 60342.9 40228.6 612203.5 304228.8 608457.2 912686 49.08212

70 0.000857143-0.0012857140.018428571 596904 103444.971468963.31429769312.2857 304228.8 608457.2 912686 18.636607

75 0.001 -0.001 0.017 639540 120685.8 80457.2 840683 304228.8 608457.2 912686 8.5648216

80 0.001125 -0.00075 0.01575 682176 135771.525 90514.35 908461.875 304228.8 608457.2 912686 0.4649754

82.5 0.001181818-0.0006363640.015181818 703494 142628.672795085.78182941208.4545 304228.8 608457.2 912686 -3.0304078

100 0.0015 0 0.012 852720 181028.7 120685.8 1154434.5 304228.8 608457.2 912686 -20.940858

7/24/2019 KUIS 2.docx


7/24/2019 KUIS 2.docx


7/24/2019 KUIS 2.docx


7/24/2019 KUIS 2.docx


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KUIS 2.docx