Rekpon 2 Formula Aco [PDF]

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q=



L1



L2



D



Tebal (L1)



= 2.2



γ



= 1537 kg/m3



ø



=



Tebal (L2)



= 2.5



γsat



= 1953 kg/m3



ø



=



c



= 0



ø



=



γ



= 1987 kg/m3



1400



kg/m2



m 29



o



m 30



o



kg/m2 31



o



¨ Keterangan : 1. Lapisan 1



: γ1 ø1



2. Lapisan 2



: γSat 2 ø2 γ2'



= 1537 kg/m3 =



29



= 1953 kg/m3 =



30 o = γSat 2 - γw = 1953 -



3. Lapisan 3



: γSat 3 ø2 γ3'



o



1000 =



953



kg/m3



987



kg/m3



= 1987 kg/m3 =



31 o = γSat 2 - γw = 1987 -



1000 =



¨ Menentukan koefisien tekanan tanah aktif dan pasif 1. Lapisan 1 (L1) Ka1 = Tan2 (45 - Ф/2)



Kp1



= Tan2 (45 + Ф/2)



= Tan2 ( 45 = 0.35



-



29 /2 )



= Tan2 ( 45 = 2.88



2. Lapisan 2 (L2) Ka2 = Tan2 (45 - Ф/2) = Tan2 ( 45 = 0.33



-



Kp2 30 /2 )



= Tan2 ( 45 = 0.32



-



Kp3 31 /2 )



29 /2 )



= Tan2 (45 + Ф/2) = Tan2 ( 45 = 3.00



3. Lapisan 3 (D) Ka3 = Tan2 (45 - Ф/2)



+



+



30 /2 )



= Tan2 (45 + Ф/2) = Tan2 ( 45 = 3.12



+



31 /2 )



¨ Menghitung tekanan tanah untuk setiap lapisan 1. Untuk kedalaman Z = 0.00 m σv0 = q =



1400



σh0 = P1 = =



kg/m2 q . Ka1



485.76



2. Untuk kedalaman Z



kg/m2 =



L1



=



2.20



m



σv1 = q + γ1 . L1 = = σh2 =



1400 + 1537.00 x 4781.40 kg/m2 P2 = σv1 . Ka2 = =



4781.40 1593.80



3. Untuk kedalaman Z σv2 = = =



2.20



=



x 0.33 2 kg/m L2



=



2.50



1400 + ( 1537.00 x 7163.90 kg/m2



2.20



m



q + γ1 . L1 + γ2' . L2



σ'h 3A = P3A= σv2 . Ka2 = 7163.90 = 2387.97 σh 3B = P3B = σv2 . Ka3



x 0.33 2 kg/m



7163.90 2293.16



x 0.32 2 kg/m



= =



¨ Menghitung kedalaman L3 P3B L3 =



)+(



953.00 x



2.50



)



L3



=



γ3' (Kp3 - Ka3) 2293.16 3.12 -



=



987.00 x ( = 0.83 m



0.32



)



¨ Menghitung luasan diagram tekanan tanah diatas dredge line A 1 = P 1 . L1 = 485.76 x 2.20 1 2



A2 =



1/2 . (P2 - P1 ). L1



3



A3 =



P 2 . L2



4



A4 =



1/2 .( P3A -P2 ). L2



5



A5 =



1/2 . P3B . L3







P



= = =



= 1068.6800 kg/m = 1/2 x 1108.04 x = 1218.84 kg/m = 1593.80 x 2.50 = 3984.50 kg/m = 1/2 x 794.17 x = 992.71 kg/m = 1/2 x 2293.16 x = 950.06 kg/m



2.20



2.5 0.83



A1 + A 2 + A 3 + A 4 + A 5 1068.68 8214.79



+ 1218.84 kg/m



+



3984.50



+



992.71



+



950.06



¨ Menghitung letak P dari L3 (z) / titik berat dari tekanan ACDE • ΣMc = P . Ž ΣMc ž = P (A • ΣMc = 1)(1/2. L1 + L2 + L3) + (A2)(1/3. L1+ L2 + L3) + (A3)(1/2. L2 + L3) + (A4)(1/3.L2+L3) + A5 . (2/3 .L3) = 1068.680 ( 1/2 2.20 + 2.50 + 0.83 ) + 1218.84 ( 1/3 2.20 + 2.50 + 3984.50 ( 1/2. 2.50 + 0.83 ) + 992.71 ( 1/3 2.50 + 0.83 + 950.06 (2/3. 0.83 ) = 19318.73 kg/m2 ΣMc 19318.73 ž = = = 2.35 m • P 8214.79 ¨ Menghitung P5 • P5 = [(q + γ1.L1 + γ2'.L2)Kp3]+ (γ3'.L3(Kp3 - Ka3)) + 953.00 x 2.50 )) x 3.12 ] =[( 1400 + 1537.00 x 2.20 0.83 ( 3.12 0.32 ) + 987.00 x 2293.16 = 22380.28 + = 24673.43 kg/m2







A1'



=



P5 γ3'(Kp-Ka)



=



24673.43 987.00 x ( 2.80



)







A2'



=



8.P γ3'(Kp-Ka)



=



65718.32 987.00 x ( 2.80



)



=



8.92



=



23.75











A3'



A4'



6.P(2.z.γ3'(Kp-Ka)+P5) γ3'2(Kp-Ka)2 49288.7 ((2 x 2.35 x 987.00 x ( 2.80 = 987.00 2 x ( 2.80 )2 1,857,693,919.54 = 7,658,973.72 = 242.55 =



P(6.z.P5 + 4.P) γ3'2(Kp-Ka)2 8214.79 (6 x 2.35 x 24673.43 + 4 x = 987.00 2 x ( 2.80 )2 3,129,887,134.32 = 7,658,973.72 = 408.66



) + 24673.43



=



8214.79 )



¨ Menghitung kedalaman L4 L44 + A1'.L43 - A2'.L42 - A3'.L4 - A4' = 0 L44 +



8.92



L43



-



23.75



L42 -



242.55



L4 -



408.66



=



0



Dengan cara coba-coba, maka L4 : Dianggap L4 (m) 5.64000 5.56350 5.56327



Hasil Persamaan 79.326 0.235 0.00307



¨ Menghitung P4 P4 = P5 + γ3' L4 (Kp-Ka)3 = 24673.43 + 987 = 40069.70 kg/m2 ¨ Menghitung P3 P3 = γ3' L4 (Kp-Ka) = 987 x 5.56 ( 2 = 15396.27 kg/m



x



5.56



2.80



Maka L4



(



2.80



)



¨ Menghitung L5 (P3 x L4) - 2.P L5 = P3 + P4 5.56 ) - 2 x ( 15396.27 x = 15396.27 + 40069.70 69224.01 = 55465.96 = 1.25 m



8214.79



)



=



5.56



m



¨ Kedalaman D aktual dan teoritis Dteorotis = L3 + L4 = =



0.83 6.39



+ m



5.56



Kedalaman dinaikkan sebesar 30% (1/3) dari D sebenarnya. Drencana



= 1.3Dteorotis = 1.3 x = 8.31



Drencana



= =



### 6.39 m



( 0.30 x 6.39 8.31 m



)



+



6.39



¨ Menghitung nilai z' (menentukan dimensi sheetpile) 2xP 0.5 Ö z' = γ3'(Kp-Ka)3 = =



16429.58 2767.49 2.44 m



0.5



¨ Menghitung momen maksimum Mmax



= P(z+z') - ((0.5.γ3'.z'2.(Kp-Ka)).(z'/3) = 8214.79 ( 2.35 + 2.44 ) - ( 0.5 x x 2.8039 x 0.8122 ) = 39334.26 6671.84 32662.42 = Kg.m



Digunakan tekanan ijin sebesar w = PZ-27



M = σijin



32662.42 17200000



162.3 x 10-5 m3



= =



172



987



MN/m2 =



0.0018990



x



2.44



2 17200000 kg/m



= 189.90 x 10-5 m3



skala = 5000 p1 = p2 =



0.097 0.319



p3a =



0.478



p3b = p5 =



0.459 4.935



p4 = p3 =



8.014 3.079



Mmax = 6.5324831 p = 1.6429581



950.06



.L2+L3) + A5 . (2/3 .L3) + 0.83 ) 0.83 )



L1 g'1 C f



= = = =



7.2 1554 0 28



m kg/m^3 kg/m^2 °



D g2 C f



= = = =



? 1965 5832 0



m kg/m^3 kg/m^2 °



l1= 1m l2= 6.2 m



g'2



=



965



a).Menghitung Koefisien tekanan Tanah - Lapis 1 Ka1 = Tan^2 = Tan^2 = 0.36 kg/m^3



- Lapis 2 Ka2 = = =



Tan^2 Tan^2 1.000



b).Menghitung tekanan Tanah - Lapis 1 s1 = ( g'1 = ( 1554 = 4039.531 - Lapis 2 s2 = = =



( g'1 ( 1554 11188.800



c).Menghitung L2 L2 = s2 g'2 ( Kp2 = 11188.800 965 ( = #DIV/0! m d).Hitung resultan gaya P di atas titik balik Lapis



Bentuk



1



2







P=



jarak garis kerja P ke E z = ∑ M



= =



P #DIV/0! #DIV/0! #DIV/0! m



e).Menghitung L3 L3^3 + 1.5



L3



=



L3^2



L3^3



+



1.5



L3^3



+



#DIV/0!



2.2



L3^2



m



f).Menghitung s 7 s7 = g'2 ( Kp2 = 965 ( = 0.000 g).Menghitung kedalaman D Dteori = L2 + = ### + = ### m Dactual



= = =



1.3 1.4 ### ### m



h).Menghitung gaya anker F = P - 1/2 = #DIV/0! = #DIV/0!



i).Menghitung z' z' =Kedalaman dari permukaan tanah 1/2 Ka1 g'1 z'^2 0.5 0.361 1554 280.523 z'^2 z'



=



6.47



m



#DIV/0!



j).Menghitung momen maksimum. Mmax = - 1/6 = 0.167 = #DIV/0! k).Modulus penampang yang diperlukan pakai type ASTM-328 sall = 172 mN/m^2 S



= = =



Mmax sall #DIV/0! 17200000 #DIV/0!



Perencanaan angkur a g'1 Ka1 f Kp1 H/u



= = = = = >



1 1554 0.361 28 2.770 1,5-2



m kg/m^3



H = a + H/u = a/h + 1.5 = 1 h h = B = H = a + = 1 + = 1.5



0.5 h 0.5



° diambil



1.5



0.5



+



®



1 m 0.5 h 0.5 m



-Menghitung besar sudut f1 dan f2 - f1 = 45 + f / 2 = 45 + 28 / 2 = 59 ° - f2 = 45 f / 2 = 45 - 28 / 2 = 31 ° -Menghitung pajang a' Tan f1 = L1 + a'



L2



Tan 59



=



7.2



a'



=



#DIV/0! 1.66



a'



=



#DIV/0! m



-Menghitung pajang b' Tan f2 = H b'



+ ### a'



1 h



=



1.5



-



0.5



®



h



=



1 1



=



a'



Tan 31



=



b'



=



1.5 0.601



b'



=



2.5



b'



= =



+



1.5 b'



m



### + 2.5 ### m



Jadi jarak plat angkur dari turap minimal



= ### m



METODE OVESEN DAN STROMANN(1972) -Menghitung beban ultimate(Pult) P'ult = 1 g'1 H^2 2 w



= = =



Kp1 Sin d'



H 1.5



- Ka1 Cos f



)



g'1



t 1 2331



1554 kg/m



+ 0.5 g'1 0.5 g'1



=



w



=



2331



=



( Kp1 Cos d'



1.503



+ 0.5 0.5



H^2 H^2 1554 1554



Ka1 Sin f



2.25 2.25



0.361



Sin 28



P'ult



=



= =



1 2



=



=



( Kp1 Cos d'



H^2



0.5 1554 2.25 11621.549 kg



- jika pasir lepas, - jika pasir Padat,



P'us =



g'1



Cov = Cov =



14 19



(



Cov + Cov +



1 H h



(



14 14



+ +



11246.66



)



1 1.5 1



(



6.3



- Ka1 Cos f



-



0.361 Cos 28



P'ult



)



11621.549



kg



-Menghitung beban yang di izinkan(Pall) FS yang digunakan untuk metode ovesen dan stromann(1972) = Pall = P'us = 11246.6608 = 5623.330 kg/m FS 2 -Menghitung jarak antar angkur S' = Pall F = 5623.330 #DIV/0! = #DIV/0! m S' H



+



B h



=



### 1.5



+



1 1



)



= #DIV/0!



2



)



Be



= Pult = = =



P'us Be 11246.66 0 0 kg



Koefisien tekanan Tanah ( (



45 45



-



( (



f 28



/ /



2 2



) )



) )



Kp1 = = =



Tan^2 Tan^2 2.77



( (



45 45



+ +



( (



f 28



/ /



2 2



) )



) )



( (



45 45



-



( (



f 0



/ /



2 2



) )



) )



Kp2 = = =



Tan^2 Tan^2 1.000



( (



45 45



+ +



( (



f 0



/ /



2 2



) )



) )



tekanan Tanah L1 ) Ka1 1554 7.2 ) 4039.531 kg/m^2



0.361



L1 ) Ka2 1554 7.2 ) 11188.800 kg/m^2



1.000



s2 - Ka2 ) 11188.800 1.000 -



1.000



)



an gaya P di atas titik balik dan letak garis kerjanya. Bentuk



P=



Gaya (s1*L1)/2=



14542.313



(s2*L2)/2=



#DIV/0!



#DIV/0!



Lengan



Momen



(L1/3)+L2= #DIV/0!



#DIV/0!



(L2)*2/3=



#DIV/0!



M=



#DIV/0!



#DIV/0!



L3^2



( l2



+



L2



)



-



3



L3^2



(



+



### )



-



3



=



0



6.2



L3^2



-



#DIV/0!



P



[



(



#DIV/0!



L1 g'2



[ ( 965 (



#DIV/0!



- Ka2 ) 1.000 kg/m^2



L3 1.000



)



2.2



kedalaman D L3 2.2



1.4 (



Dteori )



g'2 ( Kp2 - 0.5 965 kg



Ka2 ) L3^2 ( 1.000 -



aman dari permukaan tanah F = 0 z'^2 #DIV/0! #DIV/0!



#DIV/0! = 0



=



0



1.000



+ L2 ) ( ( Kp2 - Ka2 )



)



4.8



z



+



l1



)



]



=



0



7.2 + ### ) 1.000 - 1.000



( )



#DIV/0! +



1



]



momen maksimum. Ka1 g'1 z'^3 + F ( z' 0.167 0.361 1554 270.470 + #DIV/0! kg.m



-



l1 ) #DIV/0!



(



6.47



ampang yang diperlukan mN/m^2



=



#DIV/0! 17200000 #DIV/0! m^3/m



172000 kN/m^2 =



=



#DIV/0! x 10^5



17200000



m^3/m



kg/m^2



-



1



)



1



m



METODE GHALY(1997)



METODE NEELY,STUART,DAN GRAHAM(1



-Menghitung beban ultimate(Pult) A = B x h = 1 x 1 = 1 m^2 28 f = ° H = 1.5 m F = #DIV/0! kg



-Menghitung beban ultimate(Pult) H = 1.5 = h 1 B h



5.4 Tan f



x



(



H^2 A



)



^0,28



=



5.4 0.532



x



(



2.25 1



)



^0,28



=



29707.956



kg



Pult =



-Menghitung beban yang di izinkan(Pall) FS yg digunakan untuk metode ghaly(1997) Pall = Pult = 29707.9562 FS 3 -Menghitung jarak antar angkur S' = Pall F = 9902.652 #DIV/0! = #DIV/0! m



=



x



x



g'1 A



H



1554



1



= 3 9902.652 kg/m



1.5



=



1 1



=



Pult = = =



Myg g'1 13 1554 30303



-Menghitung beban yang di izinkan(Pall FS yg digunakan untuk metode neely,stua Pall = Pult FS -Menghitung jarak antar angkur S' = Pall F = 20202 #DIV/0! = #DIV/0!



=



0



,STUART,DAN GRAHAM(1973)



eban ultimate(Pult) 1.5



1



h^2 B Fs 1 1 1.5 1554 kg



eban yang di izinkan(Pall) n untuk metode neely,stuart and graham(1973) = 30303 = 20202 kg/m 1.5



rak antar angkur



20202 #DIV/0! m



=



1.5



L1



L2



D



Tebal (L1)



= 1.8



m



γ



= 1543 kg/m3



ø



=



Tebal (L2)



= 5.5



γ



= 1543 kg/m3



ø



=



c



=



ø γsat



=



30



o



m 30



o



4795 kg/m2 0



o



= 1979 kg/m3



¨ Keterangan : 1. Lapisan 1



: γ1 ø1



2. Lapisan 2



: γSat 2 ø2 γ2'



= 1543 kg/m3 =



30



= 1543 kg/m3 =



30 o = γSat 2 - γw = 1543 -



3. Lapisan 3



: γSat 3 ø2 γ3'



o



1000 =



543



kg/m3



979



kg/m3



= 1979 kg/m3 =



o 0 = γSat 2 - γw



= 1979 -



1000 =



¨ Menentukan koefisien tekanan tanah aktif dan pasif 1. Lapisan 1 (L1) Ka1 = Tan2 (45 - Ф/2) = Tan2 ( 45 = 0.33 2. Lapisan 2 (L2)



-



Kp1 30 /2 )



= Tan2 (45 + Ф/2) = Tan2 ( 45 = 3.00



+



30 /2 )



Ka2 = Tan2 (45 - Ф/2) = Tan2 ( 45 = 0.33



Kp2



-



30 /2 )



= Tan2 ( 45 = 3.00



3. Lapisan 3 (D) Ka3 = Tan2 (45 - Ф/2) = Tan2 ( 45 = 1.00



Kp3



-



0



/2 )



=



30 /2 )



+



0



/2 )



m



γ1 . L1



= 1543.00 x = 2777.40



1.80 kg/m2



σh1 = P1 = σv1 . Ka1 = 2777.40 = 925.80 2. Untuk kedalaman Z σv2 = = =



+



= Tan2 (45 + Ф/2) = Tan2 ( 45 = 1.00



¨ Menghitung tekanan tanah untuk setiap lapisan 1. Untuk kedalaman Z = L1 = 1.80 σv1



= Tan2 (45 + Ф/2)



=



x 0.33 2 kg/m L2



=



0.9258



5.50



0.4629



m



γ1 . L1 + γsat2 . L2 ( 1543.00 x 1.80 11263.90 kg/m2



)



+



( 1543.00 x



σ'h 2A = P2A= σv2 . Ka2 = 11263.90 = 3754.63 σh 2B = P2B = σv2 . Ka3



x 0.33 2 kg/m



11263.90 11263.90



x 1.00 2 kg/m



= =



5.50



3.7546



¨ Menghitung luasan diagram tekanan tanah diatas dredge line A1 = 1/2 . P1 . L1 = 1/2 x 925.80 2 3



A2 =



P 1 . L2



4



A3 =



1/2 .( P2a -P1 ). L2







P



= A1 + A 2 + A 3 = 833.22 = 13704.41



)



1.8773



x



= 833.22 kg/m = 925.80 x 5.50 = 5091.90 kg/m = 1/2 x 2828.83 x = 7779.29 kg/m



+ 5091.90 kg/m



¨ Menghitung momen statis terhadap E • ΣMc = P . Ž



+



1.80



5.5



7779.29 13.704412 6.8522058



ΣMc P • ΣMc = (A1)(1/3. L1 + L2) + (A2)(1/2. L2) + (A3)(1/3. L2 ) = 833.220 ( 1/3 1.80 + 5.50 ) + 5091.90 = 33347.40 kg/m2 ž







ž



=



=



ΣMc = P



33347.40 13704.41



=



2.43



¨ Menghitung P6 • P6 = 4c - (γ.L1 + γ2.L2) = 4 ( 4795 )-( ( 1543.00 x = 7916.10 kg/m2



( 1/2 5.50 )+



7779.29



( 1/3



m



1.80



) + ( 1543.00 x 5.50 )) 7.9161



¨ Kedalaman D aktual dan teoritis Dteorotis = P6D2 + 2 P6 D (L1+L2-l1) - 2 P (L1+L2-l1-z)



Daktual



=



7916.10



D2 +



2



7916.10



= =



7916.10 0.996



D + 101326.08 D m (dari kalkulator) 2



= 1.3Dteorotis = 1.3 x = 1.294



D( 1.80 + 5.50 -



0.9 ) - 2 13704.41



108721.67



0.996 m



¨ Menghitung Nilai F F = P - P6 D = 13704.41 7916.10 kg/m = 5823.49



0.996 5.8235



¨ Menghitung momen maksimum turap ½ P1 L1 - F + P1 (z-L1) + ½ Ka1 γ1 (z-L1)2 = 0 misal z - L1 = x ½ P1 L1 - F + P1 (x) + ½ Ka1 γ1 (x) 2 = 0 ½ x 925.80 x



1.8



-



5823.49



+



257.17 X2 + 925.80 X -4990.27 = X = 2.959 (dari kalkulator)



925.80 X + ½ x 0.33 x 1543 X2 = 0 0



Mmax = - ½ P1 L1 (x + L1/3) + F (x + lz) - P1 x/2 - ½ Ka1 γ1 x 2 (x/3) = - ½ x 925.80 x 1.8 x ( = -2965.13 + 22470.783 = 15915.9978 kg/m



2.959 + 0.6 )+ 5823.492 x ( 2.959 + 1369.56 2220.10 7.9579988869



¨ PERENCANAAN TULANGAN DAN PERENCANAAN DIMENSI Direncanakan : ϕ Tulangan Pokok, d = 16 mm Selimut Beton, sb = 40 mm



0.9



b h F'c Fy Momen Ultimate



= = = = = =



800 mm 250 mm 37 Mpa 370 Mpa 15915.9978 kg.m 159159978 N.mm



1. Menghitung tinggi efektif (d) • d = h sb = =



250 202



-



- 1/2 x



ϕp



- /2 x



16



1



40



2. Menghitung Koefisien Tahanan Penampang Mu • Rn = ϕ x b x d2 159159978 = 0.8 x 800 x 40804 = 6.0947 •



m



Fy 0.85 x F'c 370 = 0.85 x 37 = 11.7647 =



3. Rasio Penulangan •



ρ min



= = =



• ρ perlu = = =



1.4 Fy 1.4 370 0.0038 1 x m 1 x 11.765 0.0185



 1   



1



1 -



0.85 x F'c ρ • balance = Fy 0.85 x 37 = 370 = 0.0447



x



2 . m . Rn fy



1 -



β



x 0.85



• ρ max = 0.75 x ρ balance = 0.75 x 0.0447 = 0.0335



x x



2x



   



11.765 x 370



600 600 + Fy 600 600 + 370



6.095



Syarat :



ρ min < ρ perlu < ρ max 0.0038 < 0.0185 < 0.0335 Sehingga digunakan rasio (ρ perlu = 0.0185 ) 4. Luas Tulangan • As = ρ x b = 0.0185 x 800 = 2986.5750 mm2



x x



d 202



• Ast = ¼ x π x ϕ2 = ¼ x π x 16 = 201.0619 mm2 5. Jumlah Tulangan As • n = Ast 2986.5750 = 201.0619 = 14.854 buah ≈



15 buah



6. Jarak Antar Tulangan b • s = 15 1 800 = 14 = 57.14 mm ≈



57 mm



1. menghitung stability number Sn = C 1.25 (ᵧ.L1 + ᵧ. L2) = 0.5321 2. Menghitung nilai ᾳ ᾳ = L1 + L2 L1 + L2 + Dact = 0.8494 3. Menghitung flexibility numberv ( P ) modulus elastisitas E = 25742.96 MN/m2 = 25.74296 Kpa momen inersia I = 0 1 1 I = bh3 = 800 150 3 = = 12 12 225000000.00 maka P 10.9 x



10-7 (L1 + L2 + Dact)4 EI = 0.0016187894 log p = -2.79080965



0.0002



4. Menentukan Md dari hasil plot grafik ( dlm buku braja M das bab 9 hal 484 ) , maka Md= 1 Mmaks Md = 1 ### Md= #REF! ¨ Perencanaan angkur



Dalam merencanakan letak dan posisi antar angkur digunakan metode tegangan angkur, direncanakan jarak ½ L1 dari permukaan tanah. Dik : γ1 = 1543 kg/m3 ø =



30



0



Direncanakan pelat angkur bujur sangkar (B=h) teng 1962 menghasilkan metode perhitungan tahanan ultim dari tanah-tanah berbutir yang dekat dari permukaan tanah, yaitu: H/h > 1.2 - 2.0, digunakan H/h = H = H = H = H/h = 1.5 = h = H = H = =



1/2 1/2 0.9 0.9 0.9 0.9



L1 + 1/2 h 1.8 + 0.5 h + 0.5 h /h + 0.5 /h + 0.5 m



1/2 L1 + 1/2 h 1/2 1.8 + 0.5 1.35 m



1.5



h =



0.9



Be = 0.19 (H + h) + B = 0.19 ( 1.35 + 0.9 ) + 0.9 = 1.33 m Pult = P x Be = 13704.41 x = 18192.61 kg Pall = = = S' = =



Pult Fs 18192.61 2 9096.30 Kg Pall F 9096.30



1.33



0.9



b=h=



0.9



5823.49 = 1.56 m ≈



2



m



jadi , jarak spasi angkur adalah =



2



m



Menghitung momen ultimate (Pult) menggunakan metode Ovsen dan Stromen Diketahui : H = 1.35 m γ = 1543 kg/m2 ᶲ b=h ᵧ beton t Ka Kp



= = = = = =



Penyelesain : W = H.t.ᵧ beton = 1.35 x 0.15 = 486.000 kg/m



30 0.9 2400 0.15 0.333 3.000



x



o m kg/m2 m



2400



Kp sin ᵹ' = W + 1/2 ˠH^2 . Ka sin ᶲ /1/2 ˠH^2 = 486.000 + 1406.059 0.167 = 0.512 Berdasarkan grafik 9.39 (b) (Braja M. Das hal 849 ) , sehingga Pult = 1/2 ˠH^2 . (Kp cos ᵹ' + Ka cos ᶲ ) = 1406.06 x 3.689 = 5186.5 kg/m



3.4 Kp cos ᵹ'



Diasumsikan tanah pasir dgn ᶲ = 30 adalah dense sand (Cov = Pu's = Cov + 1 P' ult Cov + H/h = 20 5186.494 21.500 = 4824.65 kg/m



19



¨ Perencanaan penempatan angkur 1. Menghitung besar sudut Ф1 = 45 + Ф /2 = 45 + 30 /2 =



60 0



Ф2 = =



45 45 -



=



30 0



Ф /2 30 /2



2. Menghitung a' L1 + L2 + D Tan Ф1 =



Tan Ф1 = Tan 60



a'



8.59 a' a' = 4.962 m =



3. Menghitung a' H b' 1.35 Tan 30 = b' b' = 2.338 m Tan Ф2 =



a' + b' = =



4.96 7.30



+ m



2.34



( 1/3



5.50



13704.41 (



)



1.80 + 5.50 -



lz =



0.9 -



2.43 )



0.9



0.9 ) - 925.80 x



1.479



- ½ x



0.33 x



1543 x



2.959 2 x



0.986



0.0002



ngkur, direncanakan jarak



erhitungan tahanan ultimate



1.45



P=



L1



L2



L3



31 ton



P=



jenis tanah tebal lapisan, l1



= =



5



berat isi basah, γ Berat isi jenuh, γsat



=



16.5



kg/m3



=



-



kg/m3



Kohesi, c



=



-



kg/m2



Sudut gesek, ø jenis tanah tebal lapisan, l2



= = =



32 7



m



berat isi basah, γ Berat isi jenuh, γsat



=



-



kg/m3



=



16.7



kg/m3



Kohesi, c



=



12



kg/m2



Sudut gesek, ø jenis tanah tebal lapisan, l1



= = =



22



o



13



m



berat isi basah, γ



=



-



kg/m3



Berat isi jenuh, γsat



=



19.2



kg/m3



Kohesi, c



=



39



kg/m2



Sudut gesek, ø



m



o



o = eo = 0.7 Cc = 0.4 Lapisan Batuan



1. Perhitungan pondasi tiang tunggal Direncanakan menggunakan tiang HP 250 x 85 dik : P σbaja d1 d2 w W



= = = = = =



31 ton



=



310



kn



62000 kN/m2 254 mm 260 mm 14.4 mm 125 kg/m



¨ Luas penampang yang diperlukan P 310 A = = = σbaja 62000 ¨ Luas profil baja



0.005



m2



140 ton



Ap1 = (2 . d2 . w) + ((d1- 2.w) . w) = ( 2 x 260 x 14.4 ) + = =



10730.88 mm 0.0107



(( 254 -



m2



¨ Luas disekitar profil baja Ap2 = (d2 - w) x (d1 - 2w) = ( 260 - 14.4 ) x ( 254 = =



2 14.4 )



55309.12 mm2 0.0553



m2



¨ Luas Penampang Ap = Ap1 + Ap2 = 0.0107 + =



2 14.4 )



2



0.0660



m



0.0553 2



¨ Keliling p = 2 (d1 + d2) = 2 x ( 254 + 260 ) = 1028 mm = 1.028 m 2. Menghitung tahanan ujung (Qp) a) Metode mayerhof -lapisan 3 Lempung Qp = Nc* . Cu . Ap = 9 . Cu . Ap = 9 x 39 x 0.0660 = 23.18 Kg b) Metode Vesic -lapisan 3 Lempung Qp = Ap . qp



= Ap . Cu. Nc*



4 π (In . Irr + 1) + 1 3 2 4 = ( ln 100 + 1 )+ 3 = 10.04



Nc * =



Qp = Ap . Cu. Nc* = 0.0660 x 39 = 25.87 Kg Tabel kesimpulan nilai Qp No Lapisan Mayerhof



Vesic



x



π 2



+ 1



10.04



Rata - rata



14.4 )



3



3



23.18



25.87



3. Menghitung tekanan friksi (Qs) -Lapisan Pasir Qs = P . L1 . Fav L' = 20 D = 20 x 0.254 = 5.08 k =



1.65



(penampang H, hal. 570)



σv' = (γ1 . L1) = ( 16.5 x =



82.5



5



)



kg/m2



δ' = 0.8 ø = 0.8 x = 25.6



32



Fav = k . σv' tan δ = 1.65 x 82.5 = 65.2202 kg/m



x 0.479



2



Qs = P . L1 . Fav = 1.028 x 5 = 335.23 kg



x



65.2202



-lapisan Lempung Qs = P . L2 . Fav L' = 20 D = 20 x 0.254 = 5.08 k =



1.65



(penampang H, hal. 570)



σv' = (γ2' . L2) = ( -983 x =



-6883.1 kg/m



δ' = 0.8 ø = 0.8 x = 17.6



22



Fav = k . σv' tan δ



7 2



)



24.52



=



1.65 x



-6883.1 x 0.317



= -3602.69 kg/m2 Qs = P . L2 . Fav = 1.028 x 7 = -25924.95 kg



x -3602.69



P=



L1



L2



L3



8



ton



P=



jenis tanah tebal lapisan, l1



= =



6.5



berat isi basah, γ Berat isi jenuh, γsat



=



1750



kg/m3



=



-



kg/m3



Kohesi, c



=



120



kg/m2



Sudut gesek, ø jenis tanah tebal lapisan, l2



= = =



26



o



5.4



m



berat isi basah, γ Berat isi jenuh, γsat



=



-



kg/m3



=



1960



kg/m3



Kohesi, c



=



1800



kg/m2



Sudut gesek, ø jenis tanah tebal lapisan, l1



= = =



10



o



16



m



berat isi basah, γ



=



-



kg/m3



Berat isi jenuh, γsat



=



1970



kg/m3



Kohesi, c



=



1850



kg/m2



Sudut gesek, ø



=



9



m



o



Lapisan Batuan jumlah tiang kelompok =



2



x



2



1. Perhitungan pondasi tiang tunggal Direncanakan menggunakan tiang HP 200 x 53 dik : P σbaja d1 d2 w W



= = = = = =



8



ton



=



80



kn



62000 kN/m2 204 mm 207 mm 11.3 mm 125 kg/m



¨ Luas penampang yang diperlukan P 80 A = = = σbaja 62000 ¨ Luas profil baja



0.001



m2



90 ton



Ap1 = (2 . d2 . w) + ((d1- 2.w) . w) = ( 2 x 207 x 11.3 ) + =



6728.02



mm



=



0.0067



m2



(( 204 -



¨ Luas disekitar profil baja Ap2 = (d2 - w) x (d1 - 2w) = ( 207 - 11.3 ) x ( 204 =



2 11.3 )



35499.98 mm2



=



0.0355



m2



¨ Luas Penampang Ap = Ap1 + Ap2 = 0.0067 + = ¨ Q ijin Qijin = = =



2 11.3 )



2



0.0422



m



0.0355 2



Ap x σbaja 0.0422 x 62000 2618.1360 kN



Qijin 2618.14



> kN >



P 80



kN



Oke



¨ Keliling p = 2 (d1 + d2) = 2 x ( 204 + 207 ) = 822 mm = 0.822 m 2. Menghitung tahanan ujung (Qp) a) Metode mayerhof -lapisan 3 Lempung Qp = Nc* . Cu . Ap = 9 . Cu . Ap = 9 x 1850 x 0.0422 = 703.096 Kg b) Metode Vesic -lapisan 3 Lempung Qp = Ap . qp



= Ap . Cu. Nc*



4 π (In . Irr + 1) + 1 3 2 4 = ( ln 100 + 1 )+ 3



Nc * =



π 2



+ 1



11.3 )



=



10.04



Qp = Ap . Cu. Nc* = 0.0422 x 1850 = 784.68 Kg Tabel kesimpulan nilai Qp No Lapisan Mayerhof 3 3 703.10



x



Vesic 784.68



3. Menghitung tekanan friksi (Qs) -Lapisan Pasir Qs = P . L' . Fav L' = 15 D = 15 x 0.204 = 3.06 k =



1.65



(penampang H, hal. 570)



σv' = γ . L' = 1750 x 3.06 =



5355



kg/m2



δ'1 = 0.8 ø1 = 0.8 x = 20.8



26



δ'2 = 0.8 ø2 = 0.8 x = 8



10



Z = 0 sd L' Fav1 = k . (σv'/2) tan δ1 5355.00 = 1.65 x 2



x 0.38



= 1678.19 kg/m2 Qs1 = P . L' . Fav1 = 0.822 x 3.06 x = 4221.19 kg Z = L' sd L1 Fav2 = k . σv' tan δ1 = 1.65 x 5355 = 3356.39 kg/m



2



Qs2 = P . (L1 - L') . Fav2



x



1678.19



0.38



10.04



Rata - rata 743.89



= =



0.822 x ( 6.5 9490.79 kg



Z = L1 sd L2 Fav3 = k . σv' tan δ2 = 1.65 x 5355 = 1241.78 kg/m



3.06 )x



x 0.141



2



Qs3 = P . L2 . Fav3 = 0.822 x 5.4 x = 5512.03 kg



1241.78



Maka : Qs = Qs1 + Qs2 + Qs3 = 4221.19 + 9490.79 = 19224.01 kg -lapisan Lempung σv1 = (γ1 . L1) = ( 1750 x =



3356.39



+



5512.03



6.5 )



11375 kg/m2



σv2 = (γ1 . L1) + (γ2' . L2) = ( 1750 x 6.5 ) + ( 960 x =



16559 kg/m2



σv3 = (γ1 . L1) + (γ2' . L2) + (γ3' . L3) = ( 1750 x 6.5 ) + ( 960 x =



L1



5.4 )



21409 kg/m



5.4 ) + ( 970 x



A1 A2



L2



A3 A4



L3



σo =



A5



A2



+



5



)



2



A3



+



A4



+



A5



A2 = = =



σv1 x L2 11375 x 5.4 61425 kg/m



A3 = = =



1/2 x (σv2 - σv1) x 1/2 x 5184 x 5.4 13996.8 kg/m



A4 = = =



σv2 x L3 16559 x 5 82795 kg/m



A5 = = =



1/2 x (σv3 - σv2) x 1/2 x 4850 x 5 12125 kg/m



σo = 61425



= =



L2 13996.8 5.4



+



+ + +



L3 82795 5



+



12125



16379.02 kg/m2



Metode λ Cu = =



(



Cu2



x



(



1800



x



L2 ) + ( Cu3 L2 + L3 5.4 ) + ( 1850 5.4 + 5



x



L3 )



x



5



)



= 1824.04 kg/m2 Untuk nilai λ dari tabel 11.9 L = 17 m λ = 0.173 Fav = =



λ . (σv' + 2.cu) 0.173 x ( 16379.02 +



2 1824.04 )



= 3464.69 kg/m2 Qs = P . L . Fav = 0.822 x 16.9 x = 48130.75 kg Metode α Cu 1800 = Pa 10000



=



3464.69



Cu Pa



0.180



=



1850 10000



0.183 Maka α1 = Maka α2 =



0.872 0.786



`



Fav = α1 x Cu + α2 x Cu = 0.872 x 1800 + = 3023.70 kg/m



0.786 x



2



Qs = P . L . Fav = 0.822 x 16.9 x = 42004.64 kg



3023.70



Qs rata -rata Lempung Qs α + Qs λ σo = 2 42004.64 + 48130.75 = 2 = 45067.69 kg



1850



=



0.185



Qs Total Qs = = =



Qspasir + QsLempung 19224.01 + 45067.69 64291.70 kg



4. Menghitung Dukung Ijin Tiang Qu = Qp + Qs = 743.89 + 64291.70 = 65035.59 kg Qall



= = =



Qu Fs 65035.59 2 32517.80 Kg



Qytd = P + (Ap . L . γbaja) = 8000 + ( 0.0422 x 16.9 x = 13602.1776 Kg Syarat =



Qall 32517.80



)



> Qytd Kg > 13602.1776 Kg



5. Menghitung Penurunan Tiang Tunggal Perhitungan Empiris Dik : D = 204 mm = Qytd = 13602.1776 Kg L = 16.9 m = =



Aman



20.4



cm



1690



cm



422.28



cm2



Ap



=



0.0422



m



Ep



=



200000



Mpa = 2000000.00 kg/cm2



2



= S



7850



= = =



D 100 20.4 100 0.23 S



0.23



20000000000 kg/m2



Qytd . L Ap . Ep 13602.1776 x 1690 + 422.28 x 2000000.00 cm +



< cm




Qytd 112408.71



Kg



7850



Aman



)



7. Menghitung Penurunan Tiang Kelompok Dik : s = 0.23 cm (penurunan tiang tunggal) Bg = 81.6 cm D = 20.4 cm Sg



=



s



=



0.23



= Sg 0.46



0.46 < cm