hitung menara air
TRANSCRIPT
L A M P I R A N
Universitas Sumatera Utara
KONTROL PROFIL RANGKA MENARA
C. Berat Sendiri Profil 2L dengan Jumlah Medan (n) = 8
1. Berat Air
Volume air = 25 m³
Berat Air = 25 m³ x 1000 kg/m³ = 25 Ton
2. Berat Rangka Tangki
d. Berat Rangka Tangki
Keterangan:
Rangka tangki memakai profil L 50 50 5 dengan berat profil = 3,77 kg/m’
Panjang bentang diagonal dinding plat tangki
l² = 3,5² + 2,5²
l = 22 5,25,3 +
l = 4,3 m
Panjang batang diagonal plat datar tangki
l² = 3,5² + 3,5²
l = 22 5,35,3 +
l = 4,95 m
3,50 x 3.77 x 4 x 2 = 105,56 kg
2,50 x 3,77 x 4 = 37,70 kg
4,30 x 3,77 x 4 = 64,844 kg
4,95 x 3,77 x 1 = 18,662 kg
Berat Rangka Tangki = 226,766 kg
Universitas Sumatera Utara
= 0,2277 Ton
e. Berat plat tangki dengan tebal 10 mm = 0,01 m
Keterangan :
Tutup tangki dianggap senyawa dengan plat atas tangki
Plat dinding tangki = 2,5 x 3,5 x 0,01 x 7,85 x 4 = 2,7475 T
Plat datar tangki = 3,5 x 3,5 x 0,01 x 7,85 x 2 = 1,9233 T
= 4,6698 T
f. Berat ikutan/manusia (P) = 100 kg = 0,1 T
Jadi Berat sendiri pada tangki
= Berat air + berat rangka tangki + berat plat tangki + berat ikutan
= 25 + 0,2277 + 4,6698 + 0,1
= 29,9975 Ton ≈ 30 Ton
Berat Rangka = 0,8615 Ton
Berat sendiri pada Tangki = 30 Ton
Berat sendiri Total = Berat rangka + Berat sendiri pada tangki
= 0,8615 ton + 30 ton
= 30,8615 ton
Universitas Sumatera Utara
L M N
21 22
23 24
19 20
A
C
F
I
B
E
H
K
D
G
J
1
2
3
9
13
17
4
5
18
6
7
14
10
8 11
12
15
1625 26
29 30
27 28
O P Q
R S T
U V W
X Y Z
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
P = 7,7154 T P = 7,7154
P = 7,7154 T
X
S8
S9
Z
S11
S10
P = 7,7154 T
Jadi Berat sendiri tiap titik (P) = 4
ritotalBeratsendi = 4
8615,30 = 7,7154 Ton
Tan α = 75,1
875,1 = 46,975 º
Titik X
Σ kx = 0 Σ ky = 0
S9 = 0 T S8 - P = 0
S8 = P = 7,71545 T (tekan)
Titik Z
Σ kx = 0 Σ ky = 0
S10 = 0 T S11 - P = 0
S11 = P = 7,71545 T (tekan)
Universitas Sumatera Utara
Y
S48S47
S9 S10
U
S7
S45S8 S47
W
S12
S46S11S48
V
S44S43
S45 S46
R
S6
S41S7 S43
Titik Y
Σ kx = 0
S5 + S17 cos α – S18 cos α – S4 = 0
S47 = 0
S48 = 0
Titik U
Σ kx = 0 Σ ky = 0
S45 –S47 cos α = 0 S7 – S8 – S47 sin α = 0
S45 = 0 T S7 = S8 = 7,71545 T (tekan)
Titik W
Σ kx = 0 Σ ky = 0
S48 cos α – S46 = 0 S12 – S11 – S48 sin α = 0
S46 = 0 T S12 = S11 = 7,71545 T (tekan)
Titik V
Σ kx = 0
S46 + S43 cos α – S44 cos α – S45 = 0
S43 = 0 T
S44 = 0 T
Titik R
Σ kx = 0 Σ ky = 0
S41 –S43 cos α = 0 S6 – S7 – S47 sin α = 0
S45 = 0 T S6 = S7 = 7,71545 T (tekan)
Universitas Sumatera Utara
T
S13
S42S12S44
S
S40S39
S41 S42
O
S56
S37S6 S39
Q
S14
S38S13S40
P
S36S35
S37 S38
Titik T
Σ kx = 0 Σ ky = 0
S44 cos α – S42 = 0 S13 – S12 – S48 sin α = 0
S42 = 0 T S13 = S12 = 7,71545 T (tekan)
Titik S
Σ kx = 0
S42 + S39 cos α – S40 cos α – S41 = 0
S39 = 0 T
S40 = 0 T
Titik O
Σ kx = 0 Σ ky = 0
S37 –S39 cos α = 0 S5 – S6 – S39 sin α = 0
S37 = 0 T S5 = S6 = 7,71545 T (tekan)
Titik Q
Σ kx = 0 Σ ky = 0
S40cos α – S38= 0 S14 – S13 – S40sin α = 0
S40 = 0 T S14 = S13 = 7,71545 T (tekan)
Titik P
Σ kx = 0
S38 + S35 cos α – S36 cos α – S37 = 0
S36 = 0 T
S35 = 0 T
Universitas Sumatera Utara
L
S4
S33S5 S35
N
S15
S34S14S36
M
S32S31
S33 S34
I
S3
S29S4 S31
K
S16
S30S15S32
Titik L
Σ kx = 0 Σ ky = 0
S33 –S35 cos α = 0 S4 – S5 – S35 sin α = 0
S33 = 0 T S4 = S5 = 7,71545 T (tekan)
Titik N
Σ kx = 0 Σ ky = 0
S36cos α – S34= 0 S15 – S14 – S36sin α = 0
S34 = 0 T S15 = S14 = 7,71545 T (tekan)
Titik M
Σ kx = 0
S34 + S31 cos α – S32 cos α – S33 = 0
S31 = 0 T
S32 = 0 T
Titik I
Σ kx = 0 Σ ky = 0
S29 –S31 cos α = 0 S3 – S4 – S31 sin α = 0
S29 = 0 T S3 = S4 = 7,71545 T (tekan)
Titik K
Σ kx = 0 Σ ky = 0
S32cos α – S30= 0 S16 – S15 – S32sin α = 0
S30 = 0 T S16 = S15 = 7,71545 T (tekan)
Universitas Sumatera Utara
J
S28S27
S29 S30
F
S2
S25S3 S27
H
S17
S26S16S28
G
S24S23
S25 S26
C
S1
S21S2 S23
Titik J
Σ kx = 0
S30 + S27 cos α – S28 cos α – S29 = 0
S27 = 0 T
S28 = 0 T
Titik F
Σ kx = 0 Σ ky = 0
S25 –S27 cos α = 0 S2 – S3 – S31 sin α = 0
S25 = 0 T S2 = S3 = 7,71545 T (tekan)
Titik H
Σ kx = 0 Σ ky = 0
S28cos α – S26= 0 S17 – S16 – S28sin α = 0
S26 = 0 T S17 = S16 = 7,71545 T (tekan)
Titik G
Σ kx = 0
S26 + S23 cos α – S24 cos α – S25 = 0
S27 = 0 T
S28 = 0 T
Titik C
Σ kx = 0 Σ ky = 0
S21 –S23 cos α = 0 S1 – S2 – S21 sin α = 0
S21 = 0 T S1 = S2 = 7,71545 T (tekan)
Universitas Sumatera Utara
E
S18
S22S17S24
D
S20S19
S21 S22
Titik E
Σ kx = 0 Σ ky = 0
S24cos α – S22= 0 S18 – S17 – S24sin α = 0
S22 = 0 T S18 = S17 = 7,71545 T (tekan)
Titik D
Σ kx = 0
S22 + S19 cos α – S20 cos α – S21 = 0
S19 = 0 T
S20 = 0 T
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Berat Sendiri Untuk Profil 2L pada Jumlah Medan (n) = 8
No
Batang Berat sendiri (ton)
Tekan Tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
7,71545 7, 71545 7, 71545 7, 71545 7, 71545 7, 71545 7, 71545 7. 71545
- -
7, 71545 7, 71545 7, 71545 7, 71545 7, 71545 7, 71545 7, 71545 7, 71545
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Berat Sendiri Untuk Profil 2C pada Jumlah Medan (n) = 8
No
Batang Berat sendiri (ton)
Tekan Tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428
- -
7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Berat Sendiri Untuk Profil IWF pada Jumlah Medan (n) = 8
No
Batang Berat sendiri (ton)
Tekan Tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058
- -
7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Universitas Sumatera Utara
P2
P1
P1
P1
P1
P1
P1
P1
P1
P3
P3
P3
P3
P3
P3
P3
P3
P1
P1
P1+P2
P1
P1
P1
P1
P1
P3
P3
P3
P3
P3
P3
P3
P3
D. Akibat Berat Angin
1. Berat Angin Kiri
Luas bidang yang dikenai angin
Panjang batang tegak = 1,875 m
Panjang batang horizontal = 1,75 m
Panjang batang diagonal = 2,5648 m
Panjang profil yang dikenai angin
Batang tegak 2 . 55 . 55 . 10 = 12 cm = 0,12 m
Batang horizontal 2 . 30 . 30 . 3 = 7 cm = 0,07 m
Batang diagonal 2 . 50 . 50 5 = 11 cm = 0,11 m
Luas bidang yang dikenai angin
Batang tegak = 0,12 x 1,875 x 8 x 2 = 3,6 m²
Batang horizontal = 0,07 x 1,75 x 8 x 2 = 1,96 m²
Batang diagonal = 0,11 x 2,5648 x 8 x 2 = 4,514 m²
Luas total bidang yang dikenai angin = 10,074 m²
Universitas Sumatera Utara
L M N
21 22
23 24
19 20A
C
F
I
B
E
H
K
D
G
J
1
2
3
9
13
17
4
5
18
6
7
14
10
8 11
12
15
1625 26
29 30
27 28
O P Q
R S T
U V W
X Y Z
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
P1
P1
P1+P2
P1
P1
P1
P1
P1
P3
P3
P3
P3
P3
P3
P3
P3
P1 = 16
6,1 anginangdikenaitalbidangyginxLuastoxtekananan
= 16
074,10406,1 xx
= 40,296 kg = 0,0403 T
P2 = 2
6,1 dangginxLuasbixtekananan x 15
25,16
= 2
5,25,3406,1 xxx x 1,083
= 303,334 kg = 0,3034 T
P3 = 16
2,1 anginangdikenaitalbidangyginxLuastoxtekananan
= 16
074,10402,1 xx
= 30,222 kg = 0,03022 T
Universitas Sumatera Utara
X
S8
S9P1+P2
Z
S11
S10P3
Y
S48S47
S9 S10
U
S7
S45
S8 S47
P1
Titik X
Σ kx = 0 Σ ky = 0
P – S9 = 0 S8 = 0 T
S9 = P
S9 = 0,3437 T (tekan)
Titik Z
Σ kx = 0 Σ ky = 0
P – S10 = 0 S11 = 0
S10 = P3
S10 = 0,0302 T (tarik)
Titik Y
Σ kx = 0
S10 + S9 – S47 cos α – S48 cos α = 0
S47 cos α + S48 cos α = S9 + S10
S47 cos α + S48 cos α = 0,3437 + 0,0302
S47 + S48 = αcos
3739,0
S47 = 0,2740 T (tarik)
S48 = 0,2740 T (tekan)
Titik U
Σ kx = 0 Σ ky = 0
P + S47 cos α – S45 = 0 S8 + S47 sin α – S7 = 0
S45 = 0,0403 + 0,274 cos α S7 = 0,274 sin α
S45 = 0,2273 T (tekan) S7 = 0,20 T (tarik)
Universitas Sumatera Utara
V
S44S43
S45 S46
R
S6
S41
S7 S43
P1
TS42
S44
P3S13
S12
WS46
S48
P3S12
S11
Titik W
Σ kx = 0 Σ ky = 0
P + S48 cos α – S46 = 0 S12 + S48 sin α – S11 = 0
S46 = 0,0302 + 0,274 cos α S12 = 0,274 sin α
S46 = 0,2172 T (tarik) S12 = 0,20 T (tekan) Titik V
Σ kx = 0
S45 + S46 – S43 cos α – S44 cos α = 0
S43 cos α + S44 cos α = S45 + S46
S43 cos α + S44 cos α = 0,2273 + 0,2172
S43 + S44 = αcos
445,0
S43 = 0,3257 T (tarik)
S44 = 0,3257 T (tekan) Titik R
Σ kx = 0 Σ ky = 0
P + S43 cos α – S41 = 0 S7 + S43 sin α – S6 = 0
S41 = 0,0403 + 0,3257 cos α S6 = 0,2 + 0,3257 sin α
S41 = 0,22625 T (tekan) S6 = 0,4381 T (tarik) Titik T
Σ kx = 0 Σ ky = 0
P + S44 cos α – S42 = 0 S13 + S44 sin α – S12 = 0
S42 = 0,0302 + 0,3257 cos α S12 = 0,20 + 0,3257 sin α
S42 = 0,2524 T (tarik) S12 = 0,4381 T (tekan)
Universitas Sumatera Utara
S
S40S39
S41 S42
O
S5
S37
S6 S39
P1
QS38
S40
P3S14
S13
P
S36S35
S37 S38
Titik S
Σ kx = 0
S41 + S42 – S39 cos α – S40 cos α = 0
S39 cos α + S40 cos α = 0,2625 + 0,2524
S39 + S40 = αcos
5149,0
S39 = 0,3773 T (tarik)
S40 = 0,3773 T (tekan) Titik O
Σ kx = 0 Σ ky = 0
P + S39 cos α – S37 = 0 S6 + S39 sin α – S5 = 0
S37 = 0,0403 + 0,3773 cos α S5 = 0,4381 + 0,3773 sinα
S37 = 0,2977 T (tekan) S5 = 0,7139 T (tarik) Titik Q
Σ kx = 0 Σ ky = 0
P + S40 cos α – S38 = 0 S13 + S40 sin α – S14 = 0
S38 = 0,0302 + 0,3773 cos α S14= 0,4381 + 0,3773 sinα
S38 = 0,2876 T (tarik) S14 = 0,7139 T (tekan) Titik P
Σ kx = 0
S37 + S38 – S35 cos α – S36 cos α = 0
S35 cos α + S36 cos α = 0,2977 + 0,2876
S35 + S36 = αcos
5853,0
S35 = 0,429 T (tarik)
S36 = 0,429 T (tekan)
Universitas Sumatera Utara
L
S4
S33
S5 S35
P1
NS34
S36
P3S15
S14
M
S32S31
S33 S34
I
S3
S29
S4 S31
P1
KS30
S32
P3S16
S15
Titik L
Σ kx = 0 Σ ky = 0
P + S35 cos α – S33 = 0 S5 + S35 sin α – S4 = 0
S33 = 0,0403 + 0,429 cos α S4 = 0,7139 + 0,429 sinα
S33 = 0,333 T (tekan) S4 = 1,0275 T (tarik) Titik N
Σ kx = 0 Σ ky = 0
P + S36 cos α – S34 = 0 S14 + S36 sin α – S15 = 0
S34 = 0,0302 + 0,429 cos α S15 = 0,7139 + 0,429 sinα
S34 = 0,323 T (tarik) S15 = 1,0275 T (tekan) Titik M
Σ kx = 0
S33 + S34 – S31 cos α – S32 cos α = 0
S31 cos α + S32 cos α = 0,333 + 0,323
S31 + S32 = αcos
656,0
S31 = 0,4807 T (tarik)
S32 = 0,4807 T (tekan) Titik I
Σ kx = 0 Σ ky = 0
P + S31 cos α – S29 = 0 S4 + S31 sin α – S3 = 0
S29 = 0,0403 + 0,4807 cos α S3 = 1,0275 + 0,4807 sinα
S29 = 0,3683 T (tekan) S3 = 1,3789 T (tarik) Titik K Σ kx = 0 Σ ky = 0
P + S32 cos α – S30 = 0 S15 + S36 sin α – S16 = 0
S30 = 0,0302 + 0,4807 cos α S16 =1,0275 + 0,4807 sinα
S30 = 0,3582 T (tarik) S16 = 1,3789 T (tekan)
Universitas Sumatera Utara
J
S28S27
S29 S30
F
S2
S25
S3 S27
P1
HS26
S28
P3S17
S16
G
S24S23
S25 S26
Titik J
Σ kx = 0
S29 + S30 – S27 cos α – S28 cos α = 0
S27 cos α + S28 cos α = 0,3683 + 0,33582
S27 + S28 = αcos
7265,0
S27 = 0,5324 T (tarik)
S28 = 0,5324 T (tekan) Titik F
Σ kx = 0 Σ ky = 0
P + S27 cos α – S25 = 0 S3 + S27 sin α – S2 = 0
S25 = 0,0403 + 0,5324 cos α S2= 1,3789 + 0,5324 sinα
S25 = 0,4036 T (tekan) S2 = 1,7681 T (tarik) Titik H
Σ kx = 0 Σ ky = 0
P + S28 cos α – S26 = 0 S16 + S28 sin α – S17 = 0
S26 = 0,0302 + 0,5234 cos α S17 =1,3789 + 0,5234 sinα
S26 = 0,3935 T (tarik) S17 = 1,7681 T (tekan) Titik G
Σ kx = 0
S25 + S26 – S23 cos α – S24 cos α = 0
S23 cos α + S24 cos α = 0,4036 + 0,3935
S23 + S24 = αcos
7971,0
S23 = 0,5841 T (tarik)
S24 = 0,5841 T (tekan)
Universitas Sumatera Utara
C
S1
S21
S2 S23
P1
ES22
S24
P3S18
S17
D
S20S19
S21 S22
Titik C
Σ kx = 0 Σ ky = 0
P + S23 cos α – S21 = 0 S2 + S27 sin α – S1 = 0
S21 = 0,0403 + 0,5841 cos α S1 = 1,781 + 0,5841 sinα
S21 = 0,4388 T (tekan) S1 = 2,1951 T (tarik) Titik E
Σ kx = 0 Σ ky = 0
P + S24 cos α – S22 = 0 S17 + S28 sin α – S18 = 0
S22 = 0,0302 + 0,5841 cos α S18 =1,781 + 0,5841 sinα
S22 = 0,4287 T (tarik) S18 = 2,1951 T (tekan) Titik D
Σ kx = 0
S21 + S22 – S19 cos α – S20 cos α = 0
S19 cos α + S20 cos α = 0,4388 + 0,4287
S19 + S20 = αcos
8675,0
S19 = 0,6357 T (tarik)
S20 = 0,6357 T (tekan)
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Beban Angin Kiri Untuk Profil 2L
pada Jumlah Medan (n) = 8
No Batang
Berat sendiri (ton) Tekan Tarik
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
- - - - - - - -
0,3437 - -
0,200 0,4381 0,7139 1,0275 1,3789 1,7681 2,1951
- 0,6357 0,4388
- -
0,5841 0,4036
- -
0,5324 0,3683
- -
0,4807 0,333
- -
0,429 0,2977
- -
0,3773 0,2625
- -
0,3257 0,2273
- -
0,274
2,1951 1,7681 1,3789 1,0275 0,7139 0,4381 0,20
- - -
0,04725 - - - - - - -
0,6357 - -
0,4287 0,5841
- -
0,3935 0,5324
- -
0,3582 0,4807
- -
0,323 0,429
- -
0,2876 0,3773
- -
0,2524 0,3257
- -
0,2172 0,274
-
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Beban Angin Kiri Untuk Profil 2C
pada Jumlah Medan (n) = 8
No Batang
Berat sendiri (ton) Tekan Tarik
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
- - - - - - - -
0,3354 - -
0,1926 0,4151 0,6676 0,9502 1,2627 1,6052 1,9778
- 0,5506 0,3797
- -
0,5096 0,3517
- -
0,4685 0,3237
- -
0,4275 0,2957
- -
0,3865 0,2677
- -
0,3454 0,2397
- -
0,3044 0,2177
- -
0,2634
1,9778 1,6052 1,2627 0,9502 0,6676 0,4151 0,1926
- -
0,024 - - - - - - - -
0,5506 - -
0,3717 0,5096
- -
0,3437 0,4685
- -
0,3157 0,4275
- -
0,2872 0,3865
- -
0,2597 0,3454
- -
0,2317 0,3044
- -
0,2037 0,2634
-
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Beban Angin Kiri Profil IWF
pada Jumlah Medan (n) = 8
No Batang
Berat sendiri (ton) Tekan Tarik
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
- - - - - - - -
0,3531 - -
0,2092 0,4649 0,7673 1,1162 1,5118 1,9539 2,4426
- 0,7322 0,5058
- -
0,6685 0,4623
- -
0,6048 0,4189
- -
0,5411 0,3754
- -
0,4773 0,3319
- -
0,4136 0,2884
- -
0,3498 0,2449
- -
0,2861
2,4426 1,9539 1,5118 1,1162 0,7673 0,4649 0,2092
- -
0,0373 - - - - - - - -
0,7322 - -
0,4934 0,6685
- -
0,450 0,6048
- -
0,4065 0,5411
- -
0,3630 0,4773
- -
0,3195 0,4136
- -
0,2760 0,3498
- -
0,2325 0,2861
-
Universitas Sumatera Utara
P2
P3
P3
P1
P1
P1
P3
P3
P3
P3
P3
P3
P1
P1
P1
P1
P1
P3
P3
P1
P1
P1
P3
P3
P3
P3
P3
P2+P3
P1
P1
P1
P1
P1
2. Berat Angin Kanan
Luas bidang yang dikenai angin
Panjang batang tegak = 1,875 m
Panjang batang horizontal = 1,75 m
Panjang batang diagonal = 2,5648 m
Panjang profil yang dikenai angin
Batang tegak 2 . 55 . 55 . 10 = 12 cm = 0,12 m
Batang horizontal 2 . 30 . 30 . 3 = 7 cm = 0,07 m
Batang diagonal 2 . 50 . 50 5 = 11 cm = 0,11 m
Luas bidang yang dikenai angin
Batang tegak = 0,12 x 1,875 x 8 x 2 = 3,6 m²
Batang horizontal = 0,07 x 1,75 x 8 x 2 = 1,96 m²
Batang diagonal = 0,11 x 2,5648 x 8 x 2 = 4,514 m²
Luas total bidang yang dikenai angin = 10,074 m²
Universitas Sumatera Utara
L M N
21 2223 24
19 20A
C
F
I
B
E
H
K
D
G
J
1
2
3
9
13
17
4
5
18
6
7
14
10
8 11
12
15
1625 26
29 30
27 28
O P Q
R S T
U V W
X Y Z
31 32
33 3435 36
37 3839 40
41 4243 44
45 4647 48
P2+P3
P3
P3
P3
P3
P3
P3
P3
P1
P1
P1
P1
P1
P1
P1
P1
P1 = 16
2,1 anginangdikenaitalbidangyginxLuastoxtekananan
= 16
074,10402,1 xx
= 30,222 kg = 0,03022 T
P2 = 2
6,1 dangginxLuasbixtekananan x 15
25,16
= 2
5,25,3406,1 xxx x 1,083
= 303,334 kg = 0,3034 T
P3 = 16
6,1 anginangdikenaitalbidangyginxLuastoxtekananan
= 16
074,10406,1 xx
= 40,296 kg = 0,0403 T
Universitas Sumatera Utara
X
S8
S9P1
Z
S11
S10P2+P3
Y
S47 S48
S10S9
U S45
S47
P1S7
S8
Titik X
Σ kx = 0 Σ ky = 0
S9 - P = 0 S8 = 0 T
S9 = P
S9 = 0,0302 T (tarik)
Titik Z
Σ kx = 0 Σ ky = 0
S10 – P = 0 S11 = 0
S10 = P
S10 = 0,3437 T (tekan)
Titik Y
Σ kx = 0
S47 cos α + S48 cos α - S9 - S10 = 0
S47 cos α + S48 cos α = S9 + S10
S47 cos α + S48 cos α = 0,0302 + 0,3437
S47 + S48 = αcos
3739,0
S47 = 0,2740 T (tekan)
S48 = 0,2740 T (tarik)
Titik U
Σ kx = 0 Σ ky = 0
S45 - S47 cos α – P = 0 S7 - S8 - S47 sin α = 0
S45 = 0,0302 + 0,274 cos α S7 = 0,274 sin α
S45 = 0,2172 T (tarik) S7 = 0,20 T (tekan)
Universitas Sumatera Utara
W
S12
S46
S11S48
P3
V
S43 S44
S46S45
R S41
S43
P1S6
S7
T
S13
S42
S12S44
P3
Titik W
Σ kx = 0 Σ ky = 0
S46 – P - S48 cos α = 0 S11 + S48 sin α – S12 = 0
S46 = 0,0403 + 0,274 cos α S12 = 0,274 sin α
S46 = 0,2273 T (tekan) S12 = 0,20 T (tarik)
Titik V
Σ kx = 0
S43 cos α + S44 cos α - S45 - S46 = 0
S43 cos α + S44 cos α = S45 + S46
S43 cos α + S44 cos α = 0,2172 + 0,2273
S43 + S44 = αcos
445,0
S43 = 0,3257 T (tekan)
S44 = 0,3257 T (tarik)
Titik R
Σ kx = 0 Σ ky = 0
S41 - P - S43 cos α = 0 S6 - S7 - S43 sin α = 0
S41 = 0,0302 + 0,3257 cos α S6 = 0,2 + 0,3257 sin α
S41 = 0,2524 T (tarik) S6 = 0,4381 T (tekan) Titik T
Σ kx = 0 Σ ky = 0
S42 - P - S44 cos α = 0 S12 - S13 - S44 sin α = 0
S42 = 0,0403 + 0,3257 cos α S12 = 0,20 + 0,3257 sin α
S42 = 0,2625 T (tekan) S13 = 0,4381 T (tarik)
Universitas Sumatera Utara
S
S39 S40
S42S41
OS37
S39
P1S5
S6
Q
S14
S38
S13S40
P3
P
S35 S36
S38S37
Titik S
Σ kx = 0
S39 cos α + S40 cos α - S41 - S42 = 0
S39 cos α + S40 cos α = 0,2524 + 0,2625
S39 + S40 = αcos
5149,0
S39 = 0,3773 T (tekan)
S40 = 0,3773 T (tarik)
Titik O
Σ kx = 0 Σ ky = 0
S37 - P - S39 cos α = 0 S5 - S6 - S39 sin α = 0
S37 = 0,0302 + 0,3773 cos α S5 = 0,4381 + 0,3773 sinα
S37 = 0,2876 T (tarik) S5 = 0,7139 T (tekan)
Titik Q
Σ kx = 0 Σ ky = 0
S38 - P - S40 cos α = 0 S14 - S13 - S40 sin α = 0
S38 = 0,0403 + 0,3773 cos α S14= 0,4381 + 0,3773 sinα
S38 = 0,2977 T (tekan) S14 = 0,7139 T (tarik)
Titik P
Σ kx = 0
S35 cos α + S36 cos α - S37 + S38 = 0
S35 cos α + S36 cos α = 0,2876 + 0,2977
S35 + S36 = αcos
5853,0
S35 = 0,429 T (tekan)
S36 = 0,429 T (tarik)
Universitas Sumatera Utara
NS34
S36
P3S15
S14
LS33
S35
P1S4
S5
M
S31 S32
S34S33
I S29
S31
P1S3
S4
K
S16
S30
S15S32
P3
Titik L
Σ kx = 0 Σ ky = 0
S33 - P - S35 cos α = 0 S4 - S5 - S35 sin α = 0
S33 = 0,0302 + 0,429 cos α S4 = 0,7139 + 0,429 sinα
S33 = 0,323 T (tarik) S4 = 1,0275 T (tekan) Titik N
Σ kx = 0 Σ ky = 0
S34 - P - S36 cos α = 0 S15 - S14 - S36 sin α = 0
S34 = 0,0403 + 0,429 cos α S15 = 0,7139 + 0,429 sinα
S34 = 0,333 T (tekan) S15 = 1,0275 T (tarik) Titik M
Σ kx = 0
S31 cos α + S32 cos α - S33 - S34 = 0
S31 cos α + S32 cos α = 0,323 + 0,333
S31 + S32 = αcos
656,0
S31 = 0,4807 T (tekan)
S32 = 0,4807 T (tarik) Titik I
Σ kx = 0 Σ ky = 0
S29 - P - S31 cos α = 0 S3 - S4 - S31 sin α = 0
S29 = 0,0302 + 0,4807 cos α S3 = 1,0275 + 0,4807 sinα
S29 = 0,3582 T (tarik) S3 = 1,3789 T (tekan) Titik K Σ kx = 0 Σ ky = 0
S30 - P - S32 cos α = 0 S15 + S36 sin α – S16 = 0
S30 = 0,0403 + 0,4807 cos α S16 =1,0275 + 0,4807 sinα
S30 = 0,3683 T (tekan) S16 = 1,3789 T (tarik)
Universitas Sumatera Utara
J
S27 S28
S30S29
F S25
S27
P1S2
S3
H
S17
S26
S16S28
P3
G
S23 S24
S26S25
Titik J
Σ kx = 0
S27 cos α + S28 cos α - S29 - S30 = 0
S27 cos α + S28 cos α = 0,3582 + 0,3683
S27 + S28 = αcos
7265,0
S27 = 0,5324 T (tekan)
S28 = 0,5324 T (tarik)
Titik F
Σ kx = 0 Σ ky = 0
S25 - P - S27 cos α = 0 S2 - S3 - S27 sin α = 0
S25 = 0,0302 + 0,5324 cos α S2 = 1,3789 + 0,5324 sinα
S25 = 0,3935 T (tarik) S2 = 1,7681 T (tekan)
Titik H
Σ kx = 0 Σ ky = 0
S26 - P - S28 cos α = 0 S17 - S16 - S28 sin α = 0
S26 = 0,0403 + 0,5234 cos α S17 =1,3789 + 0,5234 sinα
S26 = 0,4036 T (tekan) S17 = 1,7681 T (tarik)
Titik G
Σ kx = 0
S23 cos α + S24 cos α - S25 - S26 = 0
S23 cos α + S24 cos α = 0,3935 + 0,4036
S23 + S24 = αcos
7971,0
S23 = 0,5841 T (tekan)
S24 = 0,5841 T (tarik)
Universitas Sumatera Utara
C S21
S23
P1S1
S2
E
S18
S22
S17S24
P3
D
S19 S20
S22S21
Titik C
Σ kx = 0 Σ ky = 0
S21 - P - S23 cos α = 0 S1 – S2 - S27 sin α = 0
S21 = 0,0302 + 0,5841 cos α S1 = 1,781 + 0,5841 sinα
S21 = 0,4287 T (tarik) S1 = 2,1951 T (tekan)
Titik E
Σ kx = 0 Σ ky = 0
S22 - P - S24 cos α = 0 S18 - S17 - S28 sin α = 0
S22 = 0,0403 + 0,5841 cos α S18 =1,781 + 0,5841 sinα
S22 = 0,4388 T (tekan) S18 = 2,1951 T (tarik)
Titik D
Σ kx = 0
S19 cos α + S20 cos α - S21 - S22 –= 0
S19 cos α + S20 cos α = 0,4287 + 0,4388
S19 + S20 = αcos
8675,0
S19 = 0,6357 T (tekan)
S20 = 0,6357 T (tarik)
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Beban Angin Kanan Untuk Profil 2L
pada Jumlah Medan (n) = 8
No Batang
Berat sendiri (ton) Tekan Tarik
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
2,1951 1,7681 1,3789 1,0275 0,7139 0,4381 0,20
- - -
0,3437 - - - - - - -
0,6357 - -
0,4388 0,5841
- -
0,4036 0,5324
- -
0,3683 0,4807
- -
0,333 0,429
- -
0,2977 0,3773
- -
0,2625 0,3257
- -
0,2273 0,274
-
- - - - - - - -
0,0302 - -
0,20 0,4381 0,7139 1,0275 1,3789 1,7681 2,1951
- 0,6357 0,4287
- -
0,5841 0,3935
- -
0,5324 0,3582
- -
0,4807 0,323
- -
0,429 0,2876
- -
0,3773 0,2524
- -
0,3257 0,2172
- -
0,274
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Beban Angin Kanan Untuk Profil 2C pada Jumlah Medan (n) = 8
No
Batang Berat sendiri (ton)
Tekan Tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
1,9778 1,6052 1,2627 0,9502 0,6676 0,4151 0,1926
- -
0,3354 - - - - - - - -
0,5506 - -
0,3797 0,5096
- -
0,3517 0,4685
- -
0,3237 0,4275
- -
0,2957 0,3865
- -
0,2677 0,3454
- -
0,2397 0,3044
- -
0,2117 0,2634
-
- - - - - - - -
0,024 - -
0,1926 0,4151 0,6676 0,9502 1,2627 1,6052 1,9778
- 0,5506 0,3717
- -
0,5096 0,3437
- -
0,4685 0,3157
- -
0,4275 0,2872
- -
0,3865 0,2597
- -
0,3454 0,2317
- -
0,3044 0,2037
- -
0,2634
Universitas Sumatera Utara
Tabel Gaya Batang Akibat Beban Angin Kanan Untuk Profil IWF pada Jumlah Medan (n) = 8
No
Batang Berat sendiri (ton)
Tekan Tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
2,4426 1,9539 1,5118 1,1162 0,7673 0,4649 0,2092
- -
0,3531 - - - - - - - -
0,7322 - -
0,5058 0,6685
- -
0,4023 0,6048
- -
0,4189 0,5411
- -
0,3754 0,4773
- -
0,3319 0,4136
- -
0,2884 0,3498
- -
0,2449 0,2861
-
- - - - - - - -
0,0373 - -
0,2092 0,4649 0,7673 1,1162 1,5118 1,9539 2,4426
- 0,7322 0,4934
- -
0,6685 0,450
- -
0,6048 0,4065
- -
0,5411 0,3630
- -
0,4773 0,3195
- -
0,4136 0,2760
- -
0,3498 0,2325
- -
0,2861
Universitas Sumatera Utara
Tabel Kombinasi Pembebanan pada Jumlah Medan (n) = 8 Untuk Profil 2L
No Batang
Beban Akibat Angin Kiri (ton)
Beban Akibat Angin Kanan (ton)
Berat sendiri (ton)
Beban Tetap (ton)
tekan tarik tekan tarik tekan tarik tekan tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
- - - - - - - -
0,3437 - -
0,200 0,4381 0,7139 1,0275 1,3789 1,7681 2,1951
- 0,6357 0,4388
- -
0,5841 0,4036
- -
0,5324 0,3683
- -
0,4807 0,333
- -
0,429 0,2977
- -
0,3773 0,2625
- -
0,3257 0,2273
- -
0,274
2,1951 1,7681 1,3789 1,0275 0,7139 0,4381 0,20
- -
0,0302 - - - - - - - -
0,6357 - -
0,4287 0,5841
- -
0,3935 0,5324
- -
0,3582 0,4807
- -
0,323 0,429
- -
0,2876 0,3773
- -
0,2524 0,3257
- -
0,2172 0,274
-
2,1951 1,7681 1,3789 1,0275 0,7139 0,4381
0,20 - -
0,3437 - - - - - - - -
0,6357 - -
0,4388 0,5841
- -
0,4036 0,5324
- -
0,3683 0,4807
- -
0,333 0,429
- -
0,2977 0,3773
- -
0,2625 0,3257
- -
0,2273 0,274
-
- - - - - - - -
0,0302 - -
0,20 0,4381 0,7139 1,0275 1,3789 1,7681 2,1951
- 0,6357 0,4287
- -
0,5841 0,3935
- -
0,5324 0,3582
- -
0,4807 0,323
- -
0,429 0,2876
- -
0,3773 0,2524
- -
0,3257 0,2172
- -
0,274
7,7154 7, 7154 7, 7154 7, 7154 7, 7154 7, 7154 7, 7154 7,7154
- -
7, 7154 7, 7154 7, 7154 7, 7154 7, 7154 7, 7154 7, 7154 7, 7154
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
9,9105 9,4835 9,0943 8,7429 8,4293 8,1535 7,9154 7,7154 0,3437 0, 3437 7, 7154 7,9154 8,1535 8,4293 8,7429 9,0943 9,4835 9,9105 0,6357 0,6357 0,4388 0,4388 0,5841 0,5841 0,4036 0,4036 0,5324 0,5324 0,3683 0,3683 0,4807 0,4807 0,333 0,333 0,429 0,429
0,2977 0,2977 0,3773 0,3773 0,2625 0,2625 0,3257 0,3257 0,2273 0,2273 0,274 0,274
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Universitas Sumatera Utara
Tabel Kombinasi Pembebanan pada Jumlah Medan (n) = 8 Untuk Profil 2C
No Batang
Beban Akibat Angin Kiri (ton)
Beban Akibat Angin Kanan (ton)
Berat sendiri (ton)
Beban Tetap (ton)
tekan tarik tekan tarik tekan tarik tekan tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
- - - - - - - -
0,3354 - -
0,1926 0,4151 0,6676 0,9502 1,2627 1,6052 1,9778
- 0,5506 0,3797
- -
0,5096 0,3517
- -
0,4685 0,3237
- -
0,4275 0,2957
- -
0,3865 0,2677
- -
0,3454 0,2397
- -
0,3044 0,2177
- -
0,2634
1,9778 1,6052 1,2627 0,9502 0,6676 0,4151 0,1926
- -
0,024 - - - - - - - -
0,5506 - -
0,3717 0,5096
- -
0,3437 0,4685
- -
0,3157 0,4275
- -
0,2872 0,3865
- -
0,2597 0,3454
- -
0,2317 0,3044
- -
0,2037 0,2634
-
1,9778 1,6052 1,2627 0,9502 0,6676 0,4151 0,1926
- -
0,3354 - - - - - - - -
0,5506 - -
0,3797 0,5096
- -
0,3517 0,4685
- -
0,3237 0,4275
- -
0,2957 0,3865
- -
0,2677 0,3454
- -
0,2397 0,3044
- -
0,2117 0,2634
-
- - - - - - - -
0,024 - -
0,1926 0,4151 0,6676 0,9502 1,2627 1,6052 1,9778
- 0,5506 0,3717
- -
0,5096 0,3437
- -
0,4685 0,3157
- -
0,4275 0,2872
- -
0,3865 0,2597
- -
0,3454 0,2317
- -
0,3044 0,2037
- -
0,2634
7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428
- -
7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428 7,7428
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
9,7206 9,3480 9,0055 8,6930 8,4104 8,1579 7,9354 7,7428 0,3354 0,3354 7, 7428 7,9354 8,1579 8,4104 8,6930 9,0055 9,3480 9,7206 0,5506 0,5506 0,3797 0,3797 0,5096 0,5096 0,3517 0,3517 0,4685 0,4685 0,3237 0,3237 0,4275 0,4275 0,2957 0,2957 0,3865 0,3865 0,2677 0,2677 0,3454 0,3454 0,2397 0,2397 0,3044 0,3044 0,2177 0,2177 0,2634 0,2634
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Universitas Sumatera Utara
Tabel Kombinasi Pembebanan pada Jumlah Medan (n) = 8 Untuk Profil IWF No
Batang
Beban Akibat Angin Kiri (ton)
Beban Akibat Angin Kanan
Berat sendiri (ton)
Beban Tetap (ton)
tekan tarik tekan tarik tekan tarik tekan tarik 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
- - - - - - - -
0,3531 - -
0,2092 0,4649 0,7673 1,1162 1,5118 1,9539 2,4426
- 0,7322 0,5058
- -
0,6685 0,4623
- -
0,6048 0,4189
- -
0,5411 0,3754
- -
0,4773 0,3319
- -
0,4136 0,2884
- -
0,3498 0,2449
- -
0,2861
2,4426 1,9539 1,5118 1,1162 0,7673 0,4649 0,2092
- -
0,0373 - - - - - - - -
0,7322 - -
0,4934 0,6685
- -
0,450 0,6048
- -
0,4065 0,5411
- -
0,3630 0,4773
- -
0,3195 0,4136
- -
0,2760 0,3498
- -
0,2325 0,2861
-
2,4426 1,9539 1,5118 1,1162 0,7673 0,4649 0,2092
- -
0,3531 - - - - - - - -
0,7322 - -
0,5058 0,6685
- -
0,4023 0,6048
- -
0,4189 0,5411
- -
0,3754 0,4773
- -
0,3319 0,4136
- -
0,2884 0,3498
- -
0,2449 0,2861
-
- - - - - - - -
0,0373 - -
0,2092 0,4649 0,7673 1,1162 1,5118 1,9539 2,4426
- 0,7322 0,4934
- -
0,6685 0,450
- -
0,6048 0,4065
- -
0,5411 0,3630
- -
0,4773 0,3195
- -
0,4136 0,2760
- -
0,3498 0,2325
- -
0,2861
7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058
- -
7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058 7,8058
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
10,2484 9,7597 9,3176 8,9220 8,5731 8,2707 8,0150 7,8058 0,3531 0,3531 7,8058 8,0150 8,2707 8,5731 8,9220 9,3176 9,7597
10,2484 0,7322 0,7322 0,5058 0,5058 0,6685 0,6685 0,4623 0,4623 0,6048 0,6048 0,4189 0,4189 0,5411 0,5411 0,3754 0,3754 0,4773 0,4773 0,3319 0,3319 0,4136 0,4136 0,2884 0,2884 0,3498 0,3498 0,2449 0,2449 0,2861 0,2861
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Universitas Sumatera Utara
2 55 55 10
Pendimensian Profil 2L Untuk Jumlah Medan (n) = 8
d. Batang Vertikal
Dari batang vertikal/batang tegak yang ada (batang
1,2,3,4,5,6,7,8,11,12,13,14,15,16,17,18) diambil yang mempunyai gaya
batang paling besar. Diantara batang-batang tersebut batang 1 dan batang
18 yang mempunyai gaya batang paling besar.
Beban Tetap Nt = 9,9105 x 10³ kg (tekan)
Lk = 187,5 cm
Syarat Batas
Taksir ω = 1,5
Fperlu ≥ 1600
5,1 10³ x 9,9105 x
Fperlu ≥ 9,291 cm²
Dicoba profil 2 L 55 55 10
F = 10,1 cm²
IX = IY = 26,3 cm4
Ix = iy = 1,62 cm
In = 11,3 cm4
ex = 1,72 cm
imin = 1,06 cm
Universitas Sumatera Utara
Kontrol tegangan tekan
Melentur ke sumbu bahan (X – X)
λx = ixlk =
62,15,187 = 115,741 ωx = 2,5853
σx = FtotalNtx xω
= 2,20
5853,2 10³ x 9,9105 x
= 1268,400 kg/cm² < 1600 kg/cm² ……..OK
Melentur ke sumbu masing-masing
λi = minnxi
lk ≤ 50
n = 06,1505,187
x = 3,53 ( ambil n = 5 )
λi = 06,155,187
x = 35,38
Melentur ke sumbu idiil
Iyt = 2 ( Iyo + F x a² )
a = ex + ½ δ dimana δ = 10 mm
= 1,72 + 0.5
= 2,22 cm
Iyt = 2 ( 26,3 + 10,1 x 2,222)
= 152,153 cm4
iyt = xFIyt
2 =
2,20153,152 = 2,74 cm
λyt = iytlk =
74,25,187 = 68,43
Universitas Sumatera Utara
t
2a
a a
c
3
3
pelat kopel
λiy = 22 i22
yt λλ + = 22 38,3522
43,68 +
= 77,035 ωiy = 1,568
σiy = Ftotal
iyNtxω =
48,3568,1 10³9,9105x x
= 769,30 kg/cm² < 1600 kg/cm² ……..OK
Pelat koppel
g) Stabilitas plat
a
Ipl2
≥ 10 nlk
In
lk/n = 55,187 = 37,5
2a = 2 x 2,22 = 4,44
44,4
312
1 th ≥ 10 5,373,11
h3 t ≥ 160,5504
taksir t = 5 mm = 0,5 cm
h ≥ 6,850 cm ambil h = 12 cm
h) Perhitungan Plat membujur
D = 0,02 x Nt
= 0,02 x 9,9105 x 10³
= 198,21 kg
Universitas Sumatera Utara
3
3
2
2
h
sx = F x a
= 10,1 x 2,22
= 22,422 cm3
L = Iyt
nlkxDxS X = 1537,152
5,37422,22 198,21 xx
= 1095,343 kg
Keseimbangan momen
L x 2a = N x C
N = C
aLx2 = 6
44,4 095,3431 x
N = 410,55 kg
i) Kontrol Pelat
Fn = 12 (0,5) – 2 (2) 0,5
= 4 cm2
In = 1/12 h3 t – 2 d (1/2 C)2 t
= 1/12 113 x 0,5 – 2 x 2 (1/2 6)2 x 0,5
= 54 cm4
Wn = h
In2
1 =
12542
1 = 9 cm3
σm = WnNxC2
1 =
96 410,552
1 xx = 136,85 kg/cm2
τd = FnL =
4 1095,343 = 273,83 kg/cm2
τi = 22 dm τσ + = 22 83,273 136,85 +
= 306 kg/cm2 < 1600 kg/cm2 . . . OK
C
Universitas Sumatera Utara
2 30 30 3
e. Batang horizontal
Dari batang horizontal yang ada (batang
9,10,21,22,25,26,29,30,33,34,37,38,41,42,45,46) diambil yang mempunyai
gaya batang paling besar. Diantara batang-batang tersebut batang 21 dan
batang 22 yang mempunyai gaya batang paling besar.
Beban Tetap Nt = 0,4388 x 10³ kg (tekan)
Lk = 175 cm
Syarat Batas
Taksir ω = 2,0
Fperlu ≥ 1600
0,2104388,0 3 xx
Fperlu ≥ 0,5485 cm²
Dicoba profil 2 L 30 30 3
F = 1,74 cm²
IX = IY = 1,41 cm4
Ix = iy = 0,90 cm
In = 0,57 cm4
ex = 0,84 cm
imin = 0,57 cm
Universitas Sumatera Utara
Kontrol tegangan tekan
Melentur ke sumbu bahan (X – X)
λx = ixlk =
90,0175 = 194,44 ωx = 7,297
σx = FtotalNtx xω
= 48,3
297,7104388,0 3 xx
= 920,092 kg/cm² < 1600 kg/cm² ……..OK
Melentur ke sumbu masing-masing
λi = minnxi
lk ≤ 50
n = 57,050
175x
= 6,14 ( ambil n = 7 )
λi = 57,07
175x
= 43,86
Melentur ke sumbu idiil
Iyt = 2 ( Iyo + F x a² )
a = ex + ½ δ dimana δ = 10 mm
= 0,84 + 0.5
= 1,34 cm
Iyt = 2 ( 1,41 + 1,74 x 1,342)
= 9,068 cm4
iyt = xFIyt
2 =
74,12068,9
x = 1,614 cm
λyt = iytlk =
614,1175 = 108,426
Universitas Sumatera Utara
t
2a
a a
c
3
3
pelat kopel
λiy = 22 i22
yt λλ + = 22 86,4322
426,108 +
= 116,961 ωiy = 2,640
σiy = Ftotal
iyNtxω =
48,364,2104388,0 3 xx
= 332,883 kg/cm² < 1600 kg/cm² ……..OK
Pelat koppel
a) Stabilitas plat
a
Ipl2
≥ 10 nlk
In
lk/n = 7175 = 25
2a = 2 x 1,34 = 2,68
68,2
312
1 th ≥ 10 2557,0
h3 t ≥ 7,332
taksir t = 5 mm = 0,5 cm
h ≥ 2,447 cm ambil h = 7 cm
b) Perhitungan Plat membujur
D = 0,02 x Nt
= 0,02 x 0,4388 x 10³
= 8,776 kg
Universitas Sumatera Utara
3
3
2
2
h
sx = F x a
= 1,74 x 1,34
= 2,3316 cm3
L = Iyt
nlkxDxS X = 068,9
253316,2 8,776 xx
= 56,413 kg
Keseimbangan momen
L x 2a = N x C
N = C
aLx2 = 2
68,2 56,413 x
N = 75,593 kg
c) Kontrol Pelat
Fn = 7 (0,5) – (2) 0,5
= 2,5 cm2
In = 1/12 h3 t – d (1/2 C)2 t
= 1/12 73 x 0,5 – 2 (1/2 2)2 x 0,5
= 13,29 cm4
Wn = h
In2
1 =
729,13
21
= 3,797 cm3
σm = WnNxC2
1 =
797,32593,752
1 xx = 19,909 kg/cm2
τd = FnL =
5,2413,56 = 22,565 kg/cm2
τi = 22 dm τσ + = 22 565,22909,19 +
= 30,092 kg/cm2 < 1600 kg/cm2 . . . OK
C
Universitas Sumatera Utara
2 50 50 5
f. Batang Diagonal
Dari batang diagonal yang ada (batang
19,20,23,24,27,28,31,32,35,36,39,40,43,44,47,48) diambil yang
mempunyai gaya batang paling besar. Diantara batang-batang tersebut
batang 19 dan batang 20 yang mempunyai gaya batang paling besar.
Beban Tetap Nt = 0,6357 x 10³ kg (tekan)
Lk = 256,479 cm
Syarat Batas
Taksir ω = 2,0
Fperlu ≥ 1600
0,2106357,0 3 xx
Fperlu ≥ 0,795 cm²
Dicoba profil 2 L 50 50 5
F = 4,80 cm²
IX = IY = 11 cm4
Ix = iy = 1,51 cm
In = 4,59 cm4
ex = 1,4 cm
imin = 0,98 cm
Universitas Sumatera Utara
Kontrol tegangan tekan
Melentur ke sumbu bahan (X – X)
λx = ixlk =
51,1479,256 = 169,854 ωx = 5,568
σx = FtotalNtx xω =
6,9568,5106357,0 3 xx
= 368,706 kg/cm² < 1600 kg/cm² ……..OK
Melentur ke sumbu masing-masing
λi = minnxi
lk ≤ 50
n = 98,050
479,256x
= 5,23 ( ambil n = 7 )
λi = 98,07
479,256x
= 37,39
Melentur ke sumbu idiil
Iyt = 2 ( Iyo + F x a² )
a = ex + ½ δ dimana δ = 10 mm
= 1,40 + 0.5
= 1,90 cm
Iyt = 2 ( 11,0 + 4,80 x 1,92)
= 56,656 cm4
iyt = xFIyt
2 =
8,42656,56
x = 2,429 cm
λyt = iytlk =
429,2479,256 = 105,590
Universitas Sumatera Utara
t
2a
a a
c
3
3
pelat kopel
λiy = 22 i22
yt λλ + = 22 39,3722
59,105 +
= 112,015 ωiy = 2,422
σiy = Ftotal
iyNtxω =
6,9422,2106357,0 3 xx
= 160,382 kg/cm² < 1600 kg/cm² ……..OK
Pelat koppel
a) Stabilitas plat
a
Ipl2
≥ 10 nlk
In
lk/n = 7479,256 = 36,64
2a = 2 x 1,9 = 3,8
8,3
312
1 th ≥ 10 64,3659,4
h3 t ≥ 57,12
taksir t = 5 mm = 0,5 cm
h ≥ 5,85 cm ambil h = 11 cm
b) Perhitungan Plat membujur
D = 0,02 x Nt
= 0,02 x 0,6357 x 103
= 12, 714 kg
Universitas Sumatera Utara
3
3
2
2
h
sx = F x a
= 4,8 x 1,9
= 9,12 cm3
L = Iyt
nlkxDxS X = 656,56
64,3612,9714,12 xx
= 74,987 kg
Keseimbangan momen
L x 2a = N x C
N = C
aLx2 = 5
80,3987,74 x
N = 56,99 kg
c) Kontrol Pelat
Fn = 11 (0,5) – 2 (2) 0,5
= 3,5 cm2
In = 1/12 h3 t – 2 d (1/2 C)2 t
= 1/12 113 x 0,5 – 2 x 2 (1/2 5)2 x 0,5
= 42,958 cm4
Wn = h
In2
1 =
11958,42
21
= 7,81 cm3
σm = WnNxC2
1 =
81,7599,562
1 xx = 18,243 kg/cm2
τd = FnL =
5,3987,74 = 21,425 kg/cm2
τi = 22 dm τσ + = 22 425,21243,18 +
= 28,14 kg/cm2 < 1600 kg/cm2 . . . OK
C
Universitas Sumatera Utara
Tabel Kombinasi Pembebanan dan Berat Total Profil 2L dengan Jumlah Medan ( n ) = 8
Batang Lk Berat Beban Angin Beban Bentuk F q Ix ix Iy iy
n λ ω σ Bobot
Sendiri Kiri Kanan Tetap Propil ( cm² )
( kg/cm )
( cm 4
) ( cm
) ( cm 4
) ( cm
) ( kg/cm²
) ( Kg )
1,2,3,4,5
6,7,8,11,12 187.5 -7715 2195.10 -2195.10
-9910.50 20.2 0.15857 26.30 1.62 152.15 2.740 5 115.74 2.585 1268.40 475.710
13,14,15 16,17,18
9,10,21,22 25,26,29,30 175 -438.80 438.80 -438.80 3.48 0.02732 1.41 0.90 9.068 1.614 7 194.440 7.297 920.092 76.490 33,34,37,38 41,42,45,46
19,20,23,24 27,28,31,32 256.48 635.70 -635.70 -635.70 9.6 0.07536 11.00 1.51 56.656 2.429 7 169.85 5.568 368.706 309.252 35,36,39,40 43,44,47,48
Total 861.453
2 30 30 3
2 55 55 10
2 50 50 5
Universitas Sumatera Utara
Tabel Kombinasi Pembebanan dan Berat Total Profil 2C dengan Jumlah Medan ( n ) = 8
Batang Lk Berat Beban Angin Beban Bentuk F q Ix ix Iy iy
n λ ω σ Bobot
Sendiri Kiri Kanan Tetap Propil ( cm² )
( kg/cm )
( cm 4
) ( cm
) ( cm 4
) ( cm
) ( kg/cm²
) ( Kg )
1,2,3,4,5
6,7,8,11,12 187.5 -7743 1977.80 -1977.80
-9720.60 14.2 0.11147 26.40 1.92 67.895 2.186 5 97.66 1.975 1352.26 334.410
13,14,15 16,17,18
9,10,21,22 25,26,29,30 175 -379.70 379.70 -379.70 10.8 0.08478 6.39 1.08 46.042 2.065 5 162.037 5.067 178.143 237.384 33,34,37,38 41,42,45,46
19,20,23,24 27,28,31,32 256.48 550.60 -550.60 -550.60 12.4 0.09734 14.10 1.50 54.886 2.104 5 170.986 5.642 250.527 399.451 35,36,39,40 43,44,47,48
Total 971.245
2 30 33 5
2 40 35 5
2 50 38 5
Universitas Sumatera Utara
Tabel Kombinasi Pembebanan dan Berat Total Profil IWF dengan Jumlah Medan ( n ) = 8
Batang Lk Berat Beban Angin Beban Bentuk F q Ix ix Iy iy
n λ ω σ Bobot
Sendiri Kiri Kanan Tetap Propil ( cm² )
( kg/cm )
( cm 4
) ( cm
) ( cm 4
) ( cm
) ( kg/cm²
) ( Kg )
1,2,3,4,5
6,7,8,11,12 187.5 -7806 2442.60 -2442.60
-10248.40 17.85 0.14012 666.00 6.11 49.50 1.660 112.95 2.462 1413.53 420.368
13,14,15 16,17,18
9,10,21,22 25,26,29,30 175 -505.80 505.80 -505.80 11.85 0.09302 187.00 3.98 14.800 1.120 156.250 4.712 201.124 260.463 33,34,37,38 41,42,45,46
19,20,23,24 27,28,31,32 256.48 732.20 -732.20 -732.20 16.84 0.13219 413.00 4.95 29.2 1.32 194.3 7.287 316.837 542.480 35,36,39,40 43,44,47,48
Total 1223.310
100 50
150 75
125 60
Universitas Sumatera Utara
1615
1211
810
14 7
618
54
17
13
9
3
2
1
J
G
D
K
H
E
B
I
F
C
A
L M N
21 22
23 24
19 20
A
C
F
I
B
E
H
K
D
G
J
1
2
3
9
13
17
4
5
18
6
7
14
10
8
11 12
15 16
QPO
2827
3029
2625
1615
12
11
8
10
14
76
18
5
4
17
13
9
3
2
1
J
G
D
K
H
E
B
I
F
C
A
2019
2423
2221
NML
Gambar Penomoran Rangka Batang Gambar Penomoran Rangka Batang Gambar Penomoran Rangka Batang
Menara Air dengan Jumlah Medan (n) = 3 Menara Air dengan Jumlah Medan (n) = 4 Menara Air dengan Jumlah Medan (n) = 5
Universitas Sumatera Utara
L M N
27 2829 30
25 26
A
C
F
I
B
E
H
K
G
J
1
2
3
9
1923
4
5
24
6
7
20
10
8
11
21 22
31 32
35 36
33 34
O P Q
D
R S T
U V W
X Y Z12
13
14
15
16
17
18
39 40
37 38
43 44
41 42
47 48
45 46
A' B' C'
51 52
49 50
53 54
L M N
27 2829 30
25 26
A
C
F
I
B
E
H
K
G
J
1
2
3
9
19
23
4
5
24
6
7
20
10
8
11
21 22
31 32
35 36
33 34
O P Q
D
R S T
U V W
12
13
14
15
161718
39 40
37 38
41 42
L M N
27 28
29 30
25 26
A
C
F
I
B
E
H
K
G
J
1
2
3
9
19
23
4
5
24
6
7
20
10
8 11
21 22
31 32
35 3633 34
O P Q
D
R S T
U V W
X Y Z
12
13
14
15
16
17
18
39 4037 38
43 4441 42
47 4845 46
Gambar Penomoran Rangka Batang Gambar Penomoran Rangka Batang Gambar Penomoran RangkaBatang Menara Air dengan Jumlah Medan (n) = 7 Menara Air dengan Jumlah Medan (n) = 8 Menara Air dengan Jumlah Medan (n) = 9
Universitas Sumatera Utara