I.
Perhitungan I.1 Desain Data
Parameter Bore Pile Fs = 3 Parameter Tanah NSPT Pile 1-8 = 17,5
Komponen Skin Resistance (Qs) Qs adalah Daya dukung akibat adhesi tanah dengan tiang (skin resistance) Qs1 = keliling lingkaran x tinggi x 0,2 x nilai NSPT = π x 1,35 x 3,5 x 0,2 x 17.5 = 51,928Ton Qs2 = keliling lingkaran x tinggi x 0,2 x nilai NSPT = π x 1,35 x 3,5 x 0,2 x 17,5 = 51,928Ton Qs3 = keliling lingkaran x tinggi x 0,2 x nilai NSPT = π x 1,35 x 3,5 x 0,2 x 17,5 = 51,928Ton Qs4 = keliling lingkaran x tinggi x 0,2 x nilai NSPT = π x 1,35 x 3,5 x 0,2 x 17,5 = 51,928Ton Qs5 = keliling lingkaran x tinggi x 0,2 x nilai NSPT = π x 1,35 x 3,5 x 0,2 x 17,5 = 51,928Ton Qs6 = keliling lingkaran x tinggi x 0,2 x nilai NSPT = π x 1,35 x 3,5 x 0,2 x 17,5 = 51,928Ton Qs7 = keliling lingkaran x tinggi x 0,2 x nilai NSPT = π x 1,35 x 3,5 x 0,2 x 17,5 = 51,928Ton Qs8 = keliling lingkaran x tinggi x 0,2 x nilai NSPT
= π x 1,35 x 3,5 x 0,2 x 17,5 = 51,928Ton Qb total = 51,928 x 8 = 415,422 Ton
Komponen ujung fondasi (Qb) Qb adalah Daya dukung oleh dasar tiang (base) Qb1 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb2 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb3 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb4 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb5 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb6 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb7 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb8 = Luas Lingkaran x (375 + 10(N-15)) = 0,25 x π x 1,352 x (375 + 10(17,5-15)) = 572,265Ton Qb total = 572,265x 8 = 4578,12 Ton
efisiensi pile group (eg) (n - 1)m + (m-1)n eg = 1 – Ø 90.m.n = 1 - tan-1 (1350/3070) x
( 4−1 ) x 2+ ( 2−1 ) x 4 90 x 4 x 2
= 0,670
Daya dukung batas (ultimate) (Qu)
Qu1 = Qs1 + Qb1 = 51,928+ 572,265 = 624,19275 Ton Qu2 = Qs2 + Qb2 = 51,928+ 572,265 = 624,19275 Ton Qu3 = Qs3+ Qb3 = 51,928+ 572,265 = 624,19275 Ton Qu4 = Qs4 + Qb4 = 51,928+ 572,265 = 624,19275 Ton Qu5 = Qs5 + Qb5 = 51,928+ 572,265 = 624,19275 Ton Qu6 = Qs6 + Qb6 = 51,928+ 572,265 = 624,19275 Ton Qu7 = Qs7 + Qb7 = 51,928+ 572,265 = 624,19275 Ton
Qu8 = Qs8 + Qb8 = 51,928+ 572,265 = 624,19275 Ton Daya dukung ijin (allowable) (Qa) Qa1 = Qu/Fk = 624,19275/3 =208,06425 Qa2 = Qu/Fk = 624,19275/3 =208,06425 Qa3 = Qu/Fk = 624,19275/3 =208,06425 Qa4 = Qu/Fk = 624,19275/3 =208,06425 Qa5 = Qu/Fk
= 624,19275/3 =208,06425 Qa6 = Qu/Fk = 624,19275/3 =208,06425 Qa7 = Qu/Fk = 624,19275/3 =208,06425 Qa8 = Qu/Fk = 624,19275/3 =208,06425 Daya dukung Pile Group Qag pile (1-8) = eg . Qa = 0,67 x 208,06425 = 139,403 Qag pile total = 139,403 x 8 =1115,224 Ton