Analisis Struktur Statis Tak Tentu

TUG AS ANALISIS STRUKTUR STATIS TAK TENTU Dosen

: Ir. Soetoyo

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Pertanyaan : a. Gambar bidang momen portal b. Gambar bidang geser c. Gambar bidang normal

1 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Inersia IAB

Faktor Kekakuan =

KBA

=

= m4

= IBC

KBC (

)(

= =

= =

= KCB =

)

m4

= ICD

=

= =

=

(

)(

)

KCD

=

m4

=

= KDC

= ICE

= = =

(

)( m4

=

) KCE

= =

IDF

= = = =

m4

KDF

= = =

2 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Faktor Distribusi µBA

µBC

=

µCB

=

=

=

= 0.12

= 0.37

=

µCD

= =

=

= 0.49

= 0.88 µCE

= = = 0.14

µDC

= = = 0.81

µDF

= = = 0.19

3 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Momen Primer MBA

==-

(

)(

)

= -2.29 tm = -2290 kgm MBC

= =

( )( )(

)

= 0.72 tm = 720 kgm MCB

= ( )( )(

=

)

= -0.48 tm = -480 kgm MCD

= =

(

)(

)

= 4.4 tm = 4400 kgm MDC

= -4400 kgm

MDF

= =

(

)( )

= 1.125 tm = 1125 kgm MFD

= -1125 kgm

4 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

5 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Perhitungan gaya dorong balok BCD

Gaya geser kolom AB

A

RB

RB

= (1500)(3.5) + MBA/L = 5250+555.14 = 5805.14 kg

B Gaya geser kolom CE MCE C

Rc RC

= MCE/LCE = 1008/5 = 201.6 kg

E

Gaya geser kolom DF RD RD

RF

∑D

D

= -(1/2P+(MDF-MFD)/LDF) = -(750+238) = -988 kg

F

= RB+RC+RD = 5018.74 kg

6 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Portal diberi simpangan sebesar ∆, sehingga timbul momen primer pada kolom BA sebesar : MBA= + 1.000 kgm MBA = ∆

= 1000 kgm

= =

(

)

=

m

MCE karena ∆ : MCE

= =

(

)

= 5794.65 kgm MDF karena ∆ : MDF

= =

(

)

= 5925.925 kgm

7 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

8 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Gaya dorong balok BCD akibat pergeseran

Kolom AB MBA A

RB

RB

= MBA/LAB = 962/3.5 = 274.86 kg

RB

= -MCE/LCE = -5293/5 = -1058.6 kg

B Kolom CE MCE RC

C

E Kolom DF MDF RD RD

D

RF

= -(MDF+MFD)/LDF = -(4971+5444)/6 = -1735.83 kg

F MFD

∑D’

= 274.86-1058.6-1735.83 = -2519.57

9 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

∑D + β∑D’

=0

5018.74 + β(-2519.57)

=0

Β

= 1.99

10 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

11 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Diagram Normal

Diagram Geser +600

+16250 +400 +750

+274.86 -16250

-5250

+750

12 Tugas Analisis Struktur Tak Tentu Syeni Hastorini

Diagram Momen -4833.18

-4689.9

+28.62 +9525.07

+7813.29

-28.62

+10182.56

13 Tugas Analisis Struktur Tak Tentu Syeni Hastorini