Perencanaan Balokku
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Transcript of Perencanaan Balokku
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I. Balok Melintang B2 25/35 (E-134) pada Lantai 2
qu = qu (beban kombinasi plat lantai 2 terbesar)
= 1172.8 kg/m2
q segitiga a = (1/3 x qu x Lx) x 2
= (1/3 * 1172,8 * 3)*2
= 2345.6 kg/m
q dinding = 0.15*1.0*1700*4
= 1020 kg/m
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q balok = b*h*2400
= 0.25*0.35*2400
= 210 kg/m
q1 total = q segitiga + q dinding + q balok
= 3575.6 kg/m
q2 total = q segitiga + q balok
= 2555.6 kg/m
P1 = Akibat balok B1 + akibat plat arah memanjang
= b*h*L*2400 + q trapesium * n * L
= 1890 + 2775.75
= 4665.75 kg
P2 = Akibat balok B1 + akibat plat arah memanjang
= b*h*L*2400 + q trapesium * n * L
= 1890 + 5551.5
= 7441.5 kg
P3 = Akibat balok B1 + akibat plat arah memanjang
= b*h*L*2400 + q trapesium * n * L
= 1890 + 2775.75
= 4665.75 kg
input beban diSAP
Output hasil dari SAP, Vu maks = 5415.11 kg
Output hasil dari SAP, Momen maksimum.
Mu tumpuan = 2707.55 kgm
= 27075500 Nmm
Mu lapangan = 1353.78 kgm
= 13537800 Nmm
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Perencanaan Penulangan Balok (B2 25/35)
B balok = 250 mm
H balok = 350 mm fy = 360 Mpa
Selimut = 40 mm f'c = 25 Mpa
Asumsi tul. Utama = 16 mm
Asumsi tul. Sengkang = 12 mm
Tinggi efektif (d) = H - selimut - tul. Sengkang - 1/2 * tul. Utama
= 290 mm
A. Tulangan Tumpuan :
Rn = Mu tumpuan
* b * d2
= 1.610
m = fy
0.85 * f'c
= 16.94
perlu =
= 0.00465
max = 0.75 * balance=
= 0.0235
min = 1.4 / fy= 0.00389
dipakai = 0.00465 min < perlu < max kondisi balance
As = * b * d
= 407.31 mm2
Digunakan tulangan 3D16 (As pasang = 602.88 mm2
)
Cek Perlu tulangan tekan (As') atau tidak
a = As * fy =
0.85*fc'*b
= 40.85 mm
Mn = As * fy * (d-a/2)
= 602.88*360*(290-40.85/2)
= 58507263 Nmm
Mn perlu = = 27075500
0.8
= 33844375 Nmm
Karena, Mn Penampang > Mn Perlu, 58507263 Nmm > 33844375 Nmm maka tidak perlu
tulangan tekan. Tetapi tetap perlu diadakan tulangan tekan dengan luasan 20% dari As
602.88 * 360
0.85 * 25 * 250
Mu(SAP2000)
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As' = 20% * As
= 81.46 mm2
Digunakan tulangan 2D13 (As pasang = 132.665 mm2
)
B. Tulangan Lapangan :
Rn = Mu lapangan
* b * d2
= 0.805
m = fy
0.85 * f'c
= 16.94
perlu =
= 0.00228
max = 0.75 * balance=
= 0.0235
min = 1.4 / fy= 0.00389
dipakai = 0.00389 min < perlu < max kondisi balance
As = * b * d
= 340.28 mm2
Digunakan tulangan 2D16 (As pasang = 401.92 mm2
)
Cek Perlu tulangan tekan (As') atau tidak
a = As * fy =
0.85*fc'*b
= 8.99 mm
Mn = As * fy * (d-a/2)
= 602.88*360*(290-40.85/2)
= 13635547 Nmm
Mn perlu = = 27075500
0.8
= 33844375 Nmm
Karena, Mn Penampang > Mn Perlu, 58507263 Nmm > 33844375 Nmm maka tidak perlu
tulangan tekan. Tetapi tetap perlu diadakan tulangan tekan dengan luasan 20% dari As
As' = 20% * As
= 68.06 mm2
Digunakan tulangan 2D13 (As pasang = 132.665 mm2
)
C. Tulangan Geser
Mu(SAP2000)
602.88 * 360
0.85 * 25 * 250
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Dari hasil perhitungan SAP 2000,
Vu maks = 5415.11 kg
= 54.15 kN
Vc = 1/6 * * fc' * b * d
= 1/6 * 0.85 * 25 *250 * 290
= 51354.1667 N
= 51.35 kN 2875
Vc = 0.6 * 60.42
= 30.8125 kN
Cek kondisi penampang geser pada balok :
Vu = 51.35 kN > Vc = 36.25 kN Maka perlu tulangan geser.
Spasi tulangan geser
S max = d/2
= 290/2 = 145 mm
diambil jarak tulangan geser = 140 mm
Av min = 0.062 * fc' * b * S / fy
= 30.14 mm2
Dipakai 8 - 140 ( 50.24 mm2)
Vs = Av * fy * d
s
= 37464.6857 N