Transcript Resonant Column

PARAMETER DINAMIK
TANAH
UJI LABORATORIUM
Uji Laboratorium
1. Resonant Column (regangan kecil, < 10-3 %)
2. Triaxial Dinamik (regangan besar, > 10-3 %)
3. Kombinasi keduanya
RESONANT COLUMN
Resonant Column
Resonant Column
Data yang diperoleh ;
1. Shear wave Velocity
2. Damping
3. Shear modulus
4. Young’s Modulus
Resonant Column
Peralatan terdiri atas
1. Resonant Colum Device ;
 Drive plate
 Resonant Cell
 Bottom/top Cap
 LVDT
2. Control Box
 Signal Conditioner System
 Function Generator Frequency
 Decay Trigger
 VCF input
 Power supply amplifier
Resonant Column
Skema Alat Uji
Resonant Column
Skema Alat Uji
Resonant Column
Skema Alat Uji
Resonant Column
1. Persiapan
 Sampel Uji (3.35cm x 7.12cm ; 7.0cm x 14.cm)
 Kalibrasi (LVDT)
2. Pemasangan Benda Uji
 Ikuti prosedur triaxial biasa
 Cairan Silikon (viscosity=50 centistokes)
 Pasang Cell RC
3. Pemberian Tekanan Cell dan Uji Konsolidasi
4. Pemberian Beban Torsi
 Pencatatan frekuensi, accelometer, dan decay
Prosedur Pengujian
Resonant Column
5. Analysis result
 Regangan geser
 Modulus geser
 Vs
 Redaman
Prosedur Pengujian
Resonant Column
Contoh Hasil Uji
Resonant Column
Contoh Hasil Uji
Resonant Column
Contoh Hasil Uji
Resonant Column
Contoh Hasil Uji
Resonant Column
Contoh Hasil Uji
Resonant Column
Vs = 2p.fn x H /(wnh/Vs)
I/I0 = (wnh/Vs) tan (wnh/Vs)
Gmax = (g/g) x Vs2
Rumus perhitungan
Resonant Column
Vs = Shear wave velocity
Gmax = Shear Modulus
I/I0 = Rasio momen inersia
H = tinggi awal sampel
Resonant Column
Hasil uji RC
Tentukan Modulus
Geser dan Vs jika
diketahui :
H = 6 inch
41
Berat volume = 105
lb/ft3
I/I0 = 0.4
Contoh Perhitungan
Resonant Column
I/I0 = (wnh/Vs) tan (wnh/Vs) = 0.4
(wnh/Vs) = 0.593
Vs = 2p.41 x 0.5 /(0.593)
= 217.09 ft/sec
Gmax = (105/32.2) x 217.092
= 153691.9 lb/ft2
Contoh perhitungan
TRIAXIAL DYNAMIC
Triaxial Dynamic
Triaxial Dynamic
Triaxial Dynamic
Triaxial Dynamic
Peralatan terdiri atas
1. Triaxial Dynamic Apparatus
 Electro magnetic valves
 Digital phase generator
 Feedback Monitor
2. Triaxial Cell
3. Plotter
Triaxial Dynamic
Esec = sdc x 100/ea
g = (1+m) x ea
Gsec = Esec / [2(1+m)]
D = Luas hysterisis loop/(4p x Luas segitiga
OAB) x 100 %
Rumus perhitungan
Triaxial Dynamic
Esec = Secant modulus (kPa)
g = Shear Strain (%)
Gsec = Shear Modulus (%)
D = Damping
ea = Regangan Vertikal (%)
sdc = Tegangan Dinamik (kPa)
m = Poisson’s Ratio
Triaxial Dynamic
Hasil uji Triaxial
Dinamik
236
Tentukan Modulus
Geser dan koefisien
Redaman jika
diketahui :
Luas loop = 4.52 kPa
Luas D = 1.65 kPa
m = 0.5
Contoh Perhitungan
Triaxial Dynamic
Esec = 236x100/1.4 = 16857 kPa
Gsec = 16857/[2(1+0.5)]= 5619 kPa
D = 4.52/(4p x 1.65) x 100 % = 21.8%
Contoh Perhitungan