PERHITUNGAN FONDASI FOOTPLAT FOOTPLAT BENTUK EMPAT EMPAT PERSEGI PANJANG [C]2010 : M. Noer Ilham
A. DATA FONDASI FOOT PLAT DATA TANAH
Kedalaman fondasi, Bera !ol"me ana#, S"d" 'ese( dalam, Ko#esi, Ta#anan (on"s raa-raa #asil /en'"ian sondir1, Nilai N #asil "i SPT
8f g f + 9+ N
2.50 $%.&0 )*.00 0.00 5.00 $3
B6 B7 # 6 7
2.20 $.30 0.*0 0.*0 0.)0
DIMENSI FONDASI
4ear fondasi ara# 6, 4ear fondasi ara# 7, Teal fondasi, 4ear (olom ara# 6, 4ear (olom ara# 7,
Posisi (olom dalam *0, e/i )0, s"d" 201
as
*0
f += f 7 g+
20.0 )0 2*
BAHAN KONSTRUKSI
K"a e(an eon, K"a lele# aa "lan'an, Bera eon er"lan', BEBAN RENCANA FONDASI
Ga7a a(sial a(ia ean erfa(or, erfa(or, Momen ara# 6 a(ia ean erfa(or, Momen ara# 7 a(ia ean erfa(or,
P" 350.000 M"6 $55.000 M"7 $)&.000
B. KAP KA PASITAS ASITAS DUKUNG TANAH 1. MENURUT TERZAGHI DAN PECK (1943)
Ka/asias d"("n' "limi ana# men"r" Ter:a'#i Ter:a'#i dan Pe+( $*)1 ;
9" + > N+ > $ ? 0.) > B @ 41 ? 8 f > g > N9 ? 0.5 > B > Ng > $ - 0.2 > B @ 41 + (o#esi ana# (N@m21 8f Kedalaman fondasi m1 g era !ol"me ana# (N@m)1 B lear fondasi m1 4 /anan' fondasi m1 S"d" 'ese( dalam,
+ 0.00 8f 2 .5 0 g $%.&0 B B7 $ .3 0 4 B7 2 .20 f )*.00 f f @ $30 > p 0.5)*$$5 a e)>p @ * - f@21>an f *.0$$*033 K/g ) > an2 *5° *5° ? $@2> f ? ))° ))°1 %2.*%&)05
N+ $@ an f > a2 @ 2 > +os2 *5 ? f@21 - $ N9 a2 @ 2 > +os 2 *5 ? f@21 N+ > an f ? $ Ng $@2 > an f > K/g @ +os2 f - $
52.&)% )&.50* )5.22&
Ka/asias d"("n' "limi ana# men"r" Ter:a'#i Ter:a'#i ;
9" +>N+>$?0.)>B@41 ? 8f >g>N9 ? 0.5>B>Ng>$-0.2>B@41 $&)2.%$ 9a 9" @ ) 5**.2* Ka/asias d"("n' ana#,
2. MENURUT MEYERHOF (195)
Ka/asias d"("n' ana# men"r" Me7er#of $5&1 ;
9a 9+ @ )) > B ? 0.) 1 @ B 2 > Kd Kd $ ? 0.)) > 8f @ B den'an,
dalam ('@+m21 #ar"s £ $.))
9+ a#anan (on"s raa-raa #asil sondir /ada dasar fondasi ('@+m2 1 B B7 B lear fondasi m1 $ .3 0 8f Kedalaman fondasi m1 8f 2 .5 0 Kd $ ? 0.)) > 8f @ B $.*53))))) Kd diamil, $ .) ) 9+ 5.00 Ta#anan (on"s raa-raa #asil sondir /ada dasar fondasi, 9a 9+ @ )) > B ? 0.) 1 @ B 2 > Kd 5.2$$ 9a 52$.$* Ka/asias d"("n' iin ana#, 3. MENURUT SKEMPTON (19!)
Ka/asias d"("n' ana# men"r" S(em/on $3&1 ;
9a $2.5 > N= > B ? 0.) 1 @ B 2 > Kd N= CN > N den'an, CN 2 @ $ ? / o @ /r 1 Kd $ ? 0.)) > 8f @ B 8f B /o /r CN N=
Kedalaman fondasi m1 lear fondasi m1 e(anan overburden efe(if, e'an'an efe(if referensi, fa(or (ore(si overburden, nilai SPT er(ore(si,
Ka/asias d"("n' iin ana#,
dalam (N@m2 1
#ar"s £ $.))
8f 2 .5 0 B B7 $ .3 0 /o 8f > g ** /r $00 CN 2 @ $ ? / o @ /r 1 $.) N= CN > N 25.00 Kd $ ? 0.)) > 8f @ B $.*53))))) Kd 8iamil, $ .) )
9a $2.5 > N= > B ? 0.) 1 @ B 2 > Kd
5&5.%$
4. KAPASITAS DUKUNG TANAH YANG DIPAKAI
Ka/asias d"("n' ana# men"r" Ter:a'#i dan Pe+( ; Ka/asias d"("n' ana# men"r" Me7er#of ; Ka/asias d"("n' ana# men"r" S(em/on ; Ka/asias d"("n' ana# 7an' di/a(ai ;
9a 9a 9a 9a
5**.2* 52$.$* 5&5.%$ 52$.$*
C. KONTROL TEGANGAN TANAH
A B6 > B7 4"as dasar foo /la, D6 $@& > B7 > B62 Ta#anan momen ara# 6, D7 $@& > B6 > B72 Ta#anan momen ara# 7, : 8f - # Tin''i ana# di aas foo /la, 9 # > g+ ? : > g Te(anan a(ia era foo /la dan ana#, E(senrisias /ada fondasi ; e6 M"6 @ P" 0.$32* m B6 @ & 0.)&&% m " e7 M"7 @ P" 0.$&00 m B7 @ & 0.)000 m " Te'an'an ana# ma(sim"m 7an' eradi /ada dasar fondasi ;
).&00 $.*520 $.$330 2 .$ 0 *&.5&0
9ma6 P" @ A ? M"6 @ D6 ? M"7 @ D7 ? 9 *32.*)* 9ma6 " 9a AMAN (OK)
Te'an'an ana# minim"m 7an' eradi /ada dasar fondasi ;
9min P" @ A - M"6 @ D6 - M"7 @ D7 ? 9 9min
#
$
).%
%&' %*&+, %-.%&,' (OK
D. GAYA GESER PADA FOOT PLAT 1. TINAUAN GESER ARAH /
d= Jara( /"sa "lan'an er#ada/ sisi l"ar eon, d # - d= Teal efe(if foo /la, a6 B6 - 6 - d 1 @ 2 Jara( id. (riis er#ada/ sisi l"ar foo /la, Te'an'an ana# /ada idan' (riis 'eser ara# 6,
0.0%5 0.)25 0.%)3
96 9min ? B6 - a61 @ B6 > 9ma6 - 9min1 ))*.$$$ "6 96 ? 9ma6 - 96 1 @ 2 - 9 > a 6 > B7 *30.$%) Ga7a 'eser ara# 6, B7 4ear idan' 'eser "n"( ina"an ara# 6, $300 d Teal efe(if foo/la, )25 b+ 6 @ 7 $.)))) Rasio sisi /anan' #d. sisi /ende( (olom, K"a 'eser foo /la ara# 6, diamil nilai er(e+il dari + 7an' di/erole# dari /ers.s. ;
+ $ ? 2 @ b+ > f += > > d @ & > $0-) + as > d @ ? 2 > f += > > d @ $2 > $0-) + $ @ ) > f += > > d > $0-) + 8iamil, ("a 'eser foo /la, f
$00.03) 20$0.53 3%2.0&% 3%2.0&% 0 .% 5 &5*.050
S7ara 7an' #ar"s di/en"#i,
f * + &5*.050
≥
#
"6 *30.$%)
AMAN (OK)
2. TINAUAN GESER ARAH Y
d= Jara( /"sa "lan'an er#ada/ sisi l"ar eon, d # - d= Teal efe(if foo /la, a7 B7 - 7 - d 1 @ 2 Jara( id. (riis er#ada/ sisi l"ar foo /la, Te'an'an ana# /ada idan' (riis 'eser ara# 7,
0.035 0.)$5 0.5)
97 9min ? B7 - a71 @ B7 > 9ma6 - 9min1 ))&.%) "7 97 ? 9ma6 - 97 1 @ 2 - 9 > a 7 > B6 *%).2*0 Ga7a 'eser ara# 7, B6 4ear idan' 'eser "n"( ina"an ara# 7, 2200 d Teal efe(if foo/la, )$5 b+ 6 @ 7 $.)))) Rasio sisi /anan' #d. sisi /ende( (olom, K"a 'eser foo /la ara# 7, diamil nilai er(e+il dari + 7an' di/erole# dari /ers.s. ;
+ $ ? 2 @ b+ > f += > > d @ & > $0-) + as > d @ ? 2 > f += > > d @ $2 > $0-) + $ @ ) > f += > > d > $0-) + 8iamil, ("a 'eser foo /la, f
$2$.)2 $5.&$ $0)).0&) $0)).0&) 0 .% 5 %%*.%3
f * + %%*.%3
≥
#
"6 *%).2*0
AMAN (OK)
3. TINAUAN GESER DUA ARAH (PONS)
Jara( /"sa "lan'an er#ada/ sisi l"ar eon, Teal efe(if foo /la, 4ear idan' 'eser /ons ara# 6, 4ear idan' 'eser /ons ara# 7, Ga7a 'eser /ons 7an' eradi,
d= d # - d= +6 6 ? d +7 7 ? d
0.035 0.)2 0.%$5 0.&$5
"/ B6 > B7 - +6 > +7 1 > 9 ma6 ? 9min 1 @ 2 - 9 %55.&$5 A/ 2 > + 6 ? +7 1 > d 0.3)3 4"as idan' 'eser /ons, / 2 > + 6 ? +7 1 2.&&0 4ear idan' 'eser /ons, b+ 6 @ 7 $.)))) Rasio sisi /anan' #d. sisi /ende( (olom, Te'an'an 'eser /ons, diamil nilai er(e+il dari f / 7an' di/erole# dari /ers.s. ; f / $ ? 2 @ b+ > f += @ & $.3&) f / as > d @ / ? 2 > f += @ $2 2.5$$ f / $ @ ) > f += $.*$ f / Te'an'an 'eser /ons 7an' dis7ara(an, $.*$
n/ ≥ S7ara ; # )&.30$
f > n/ )&.30$
≥
#
f f > n/ f f > > A/ > f / > $0)
0 .%5 )&.30
"/ %55.&$5
AMAN (OK)
P" 350.000
AMAN (OK)
E. PEMBESIAN FOOTPLAT 1. TULANGAN LENTUR ARAH /
Jara( e/i (olom er#ada/ sisi l"ar foo /la, Te'an'an ana# /ada e/i (olom,
a6 B6 - 6 1 @ 2
0.00
96 9min ? B6 - a61 @ B6 > 9ma6 - 9min1 )0$.*)0 Momen 7an' eradi /ada /la fondasi a(ia e'an'an ana#,
M"6 $@2 > a62 > 96 ? 2@) > 9 ma6 - 96 1 - 9 > B 7 2%).%&3 B7 4ear /la fondasi 7an' diina", $300 # Teal /la fondasi, *00 d= Jara( /"sa "lan'an #d. sisi l"ar eon, %5 d # - d= Teal efe(if /la, )25 f += K"a e(an eon, 20 f 7 K"a lele# aa "lan'an, )0 Es 2.00E?05 Mod"l"s elasis aa,
b$
0.35 r b$> 0.35 > f +H@ f 7 > &00 @ &00 ? f 7 1 0.022*55)2 f r > f 7 > $->0.%5> r > f 7 @ 0.35 > f +H 1 5.2 Mn M"6 @ f )*2.2$0 Rn Mn > $0& @ > d 2 1 $.%2
Rn
Rma6
(OK)
Rasio "lan'an 7an' di/erl"(an,
r 0.35 > f +H @ f 7 > $ - $ 2 > Rn @ 0.35 > f +H 1 L 0.00* rmin 0.0025 Rasio "lan'an minim"m, r 0.00* Rasio "lan'an 7an' di'"na(an, As r > > d 23&0.)0 4"as "lan'an 7an' di/erl"(an, 8 $& 8iameer "lan'an 7an' di'"na(an, s p @ * > 82 > @ As Jara( "lan'an 7an' di/erl"(an, $2% sma6 Jara( "lan'an ma(sim"m, 20 0 s Jara( "lan'an 7an' di'"na(an, $2% 8 $& $20 8i'"na(an "lan'an, 0 As p @ * > 82 > @ s )0$5.) 4"as "lan'an er/a(ai, 2. TULANGAN LENTUR ARAH Y
Jara( e/i (olom er#ada/ sisi l"ar foo /la, Te'an'an ana# /ada e/i (olom,
a7 B7 - 7 1 @ 2
0.%50
97 9min ? B7 - a71 @ B7 > 9ma6 - 9min1 23.0%3 Momen 7an' eradi /ada /la fondasi a(ia e'an'an ana#,
M"7 $@2 > a72 > 97 ? 2@) > 9 ma6 - 97 1 - 9 > B 6 B6 4ear /la fondasi 7an' diina", # Teal /la fondasi, d= Jara( /"sa "lan'an #d. sisi l"ar eon, d # - d= Teal efe(if /la, f += K"a e(an eon, f 7 K"a lele# aa "lan'an, Es Mod"l"s elasis aa, b$ 0.35 > f +H@ f 7 > &00 @ &00 ? f 7 1 f r > f 7 > $->0.%5> r > f 7 @ 0.35 > f +H 1 Mn M"7 @ f Rn Mn > $0& @ > d 2 1 Rn Rma6 (OK)
2)$.&%* 2200 *00 35 )$5 20 )0 2.00E?05 0.35 0.022*55)2 0.30 5.2 23.52 $.)2&&$
Rasio "lan'an 7an' di/erl"(an,
r 0.35 > f +H @ f 7 > $ - $ 2 > Rn @ 0.35 > f +H 1 L 0.00)5 rmin 0.0025 Rasio "lan'an minim"m, r 0.00)5 Rasio "lan'an 7an' di'"na(an, As r > > d 2*5%.22 4"as "lan'an 7an' di/erl"(an, 8 $& 8iameer "lan'an 7an' di'"na(an, s p @ * > 82 > @ As Jara( "lan'an 7an' di/erl"(an, $30 sma6 Jara( "lan'an ma(sim"m, 20 0 s Jara( "lan'an 7an' di'"na(an, $30 8 $& $30 0 8i'"na(an "lan'an, As p @ * > 82 > @ s 2*5%.*2 4"as "lan'an er/a(ai,
3. TULANGAN SUSUT
Rasio "lan'an s"s" minim"m, 4"as "lan'an s"s" ara# 6, 4"as "lan'an s"s" ara# 7, 8iameer "lan'an 7an' di'"na(an,
rsmin As6 rsmin> d > B6 As7 rsmin> d > B7
0.00$* 3$.000 %0.200 $2
s6 p @ * > Æ2 > B7 @ As6 Jara( "lan'an s"s" ara# 6, 2* s6,ma6 Jara( "lan'an s"s" ma(sim"m ara# 6, 2 00 s6 Jara( "lan'an s"s" ara# 6 7an' di'"na(an, 200 s7 p @ * > Æ2 > B6 @ As7 Jara( "lan'an s"s" ara# 7, 25& s7,ma6 Jara( "lan'an s"s" ma(sim"m ara# 7, 2 00 s7 Jara( "lan'an s"s" ara# 7 7an' di'"na(an, 200 Æ $2 200 0 8i'"na(an "lan'an s"s" ara# 6, Æ $2 200 8i'"na(an "lan'an s"s" ara# 7, 0
m (N@m) ° (Pa ('@+m2
m m m m m
MPa MPa (N@m) (N (Nm (Nm
° m (N@m) m m ° rad
(N@m2 (N@m2
m m # 1.33
('@+m2 ('@+m2 (N@m2
m m (N@m2 (N@m2
# 1.33
(N@m2
(N@m2 (N@m2 (N@m2 (N@m2
m2 m) m) m (N@m2 (OK) (OK)
(N@m2
(N@m2 )
m m m (N@m2 (N mm mm
(N (N (N (N (N
m m m (N@m2 (N mm mm
(N (N (N (N (N
m m m m (N m2 m
MPa MPa MPa MPa
(N
m (N@m2 (Nm mm mm mm mm MPa MPa MPa
(Nm
mm2 mm mm mm mm mm2
m
(N@m2 (Nm mm mm mm mm MPa MPa MPa
(Nm
mm2 mm mm mm mm mm2
mm2 mm2 mm mm mm mm mm mm mm
