Tegangan akibat handling atau pengangkatan sewaktu pemasangan pelat Hollow Core seperti gambar di bawah
fkub 400
kg cm
2 =
Mutu beton K400 Momen tahanan Sx
fc
0.83
fkub ⋅
332
kg cm
2 ⋅
= =
Sx 0.5 I cx
h
2 2.881 10
3 ×
cm 3
⋅ =
=
BJ_beton
2400
kg m
3 =
ap Lsl
6m =
= tp
0.2 m ⋅
= Ft_ijin
0.5 fc
⋅ kg
cm 2
⋅ 9.11
kg cm
2 ⋅
= =
bp bw
1.2m =
=
w h BJ_beton
⋅
480
kg m
2 =
=
Mx 0.0107 w
⋅ ap
⋅ bp
2 ⋅
44.375 kg m ⋅
⋅ =
= My
0.0107 w ⋅
ap 2
⋅ bp
⋅ 221.875 kg m
⋅ ⋅
= =
Ft My
Sx 7.702
kg cm
2 ⋅
= =
Tegangan_tarik_beton MEMENUHI
Ft Ft_ijin
if TI DAK MEMENUHI otherwise
= Tegangan_tarik_beton
MEMENUHI =
58
Diameter kabel yang digunakan sewaktu pengangkatan
d 3
8 in
⋅ 9.525 mm
⋅ =
=
untuk diameter kabel pada tabel 3.3 untuk 1 kabel
Pijin_kabel 3.6 kip
⋅ 16 kN
⋅ =
= Pi
Pijin_kabel g
1633kg =
=
dalam satuan kg
Berat total hollow Core
Wc ap bp
⋅ tp
⋅ BJ_beton
⋅ 3456kg
= =
karena ada 4 kabel maka masing-masing kabel memikul
Pkabel Wc
4 864kg
= =
d 3
8 in
⋅ 9.525 mm
⋅ =
=
digunakan kabel diameter
Pkabel Pi
59
1. Penampang HCS per satu meter lebar :
Tinggi Penampang HCS
h 200 mm
⋅ =
Tinggi topping
htop 50 mm
⋅ =
Lebar Penampang
bw 1200 mm
⋅ =
Ac Acx
0.103m 2
= =
Luas Penampang
I c I cx
5.761 10
8 ×
mm 4
⋅ =
=
Momen Inersia
Cb h
2 =
Cb 100 mm
⋅ =
Garis Berat Bawah
Ct 100 mm
⋅ =
Garis Berat Top
Ct h
Cb −
= St
I c Ct
= St
5761473.684 mm 3
⋅ =
Sec. Modulus Top
Sb I c
Cb =
Sb 5761473.684 mm
3 ⋅
=
Sec. Modulus Bottom
2. Material
fkub 400 kgf
⋅ cm
2
−
⋅ =
K-400 a. Beton :
fc 0.83 fkub
⋅ =
fc 33.2 Mpa
⋅ =
fci 0.65 fc
⋅ =
fci 21.58 Mpa
⋅ =
Fci 0.6
− fci
⋅ =
Fci 12.948
− Mpa
⋅ =
Fti 0.25
fci Mpa ⋅
⋅ =
Fti 1.161 Mpa
⋅ =
Fc 0.45
− fc
⋅ =
akibat prategang + beban mati
Fc 14.94
− Mpa
⋅ =
Fct 0.6
− fc
⋅ =
akibat prategang + beban total
Fct 19.92
− Mpa
⋅ =
Ft 0.5
fc Mpa ⋅
⋅ =
Ft 2.881 Mpa
⋅ =
Ec 4700
fc Mpa ⋅
⋅ =
Ec 27081.137 Mpa
⋅ =
Eci 4700
fci Mpa ⋅
⋅ =
Eci 21833.511 Mpa
⋅ =
b. Kabel Prategang
fpu 2.357 10
5 ×
psi ⋅
= fpu
1625 Mpa ⋅
= fpy
1.462 10 3
× Mpa
⋅ =
fpy 0.9fpu
= fpi
975 Mpa ⋅
= fpi
0.6 fpu ⋅
= fpeff
780 Mpa ⋅
= fpeff
0.8 fpi ⋅
= n
5 =
Dia 6 mm
⋅ =
Diameter Tendon
A1 28.274 mm
2 ⋅
= A1
1 4
π ⋅
Dia 2
⋅ =
Luas per tendon efektif
e 75 mm
⋅ =
Eksentrisitas
e 0.5 h
⋅ 25 mm
⋅ −
=
60
c. Tulangan Baja
Wiremesh
fy 390 MPa
⋅ =
BJTP Polos
fyp 240 MPa
⋅ =
BJTD DeformUlir
fyd 390MPa
=
Perhitungan gaya dalam
γ
c
24
kN m
3 =
Berat volum beton normal Faktor Reduksi Lentur
φ 0.9
= Qslb
Ac γ
c ⋅
2.471 kN
m ⋅
= =
Pelat
Mslb 1
8 Qslb
⋅ Lsl
2 ⋅
11.12 kN m ⋅
⋅ =
= Qtop
htop bw ⋅
γ c
⋅ 1.44
kN m
⋅ =
=
Topping
Qtb 1
kN m
=
Tambahan
Qdlt Qslb
Qtop +
Qtb +
4.911 kN
m ⋅
= =
Qll 3
kN m
⋅ =
B. Hidup
Q Qdlt
Qll +
7.91 kN
m ⋅
= =
a. Perpendekan elastis
Eci 21833.51 MPa
⋅ =
Pi_kabel 0.7 n
⋅ A1
⋅ fpu
⋅ 160.81 kN
⋅ =
= Mg
1 8
− Qdlt
⋅ Lsl
2 ⋅
22.1 −
kN m ⋅
⋅ =
= Es
2.1 10 5
MPa ⋅
⋅ =
Kes 1
=
untuk batang pratarik
Kcir 0.9
=
untuk batang pratarik
fcir Kcir
Pi_kabel Ac
Pi_kabel e 2
⋅ I c
+
⎛ ⎜
⎝ ⎞
⎟ ⎠
⋅ Mg e
⋅ I c
−
5.7
MPa ⋅
= =
ES Kes
Es Eci
⋅ fcir
⋅ 54.78 MPa
⋅ =
=
61
b. Rangkak beton
Kcr 2
=
untuk batang pratarik dengan berat normal
Msd 1
8 Qll
⋅ Lsl
2 ⋅
13.5 kN m ⋅
⋅ =
= fcds
Msd e ⋅
I c 1.757 MPa
⋅ =
= fcir
fcds −
3.94 MPa ⋅
=
CR Kcr
Es Eci
⋅ fcir
fcds −
75.756 MPa ⋅
= =
c. Susut beton
Ac 102947.37 mm
2 ⋅
= Luas
Keliling
Sc 2 bw
h +
⋅ 2800 mm
⋅ =
= Ac
Sc 3.677 cm
⋅ =
Luas keliling
Kss 1
= RH
0.70 =
atau 70 gunakan
Ksh 1
= ε
s fy
Es 0.002
= =
SH ε
s Ksh ⋅
Es ⋅
Kss ⋅
1 RH
− ⋅
117 MPa ⋅
= =
d. Relaksasi baja
Untuk G270 low relaxation
Kre 5000psi
34.47 MPa ⋅
= =
J 0.040
=
untuk fsifpu = 0.7
C 0.7
= RE
Kre J SH
CR +
ES +
⋅ −
[ ] C
⋅ 17.2 MPa
⋅ =
= Loss
ES CR
+ SH
+ RE
+ fpu
100 ⋅
16.3 =
=
ambil losses = 20 total losseskehilangan
62