Lecture 4
References Braja M Das, Principal of Geotechnical Engineering, fourth edition, PWS Publishing Company, 1998, Boston Muni Budu, Soil Mechanics and Foundations, Foundations , 2nd edition, John Wiley & Sons, 2007, USA R.F. Craig, Soil Mechanics, Mechanics, (English & terjemahan Prof.Dr.Ir Budi S Supandji) Cernica, J.N., Soil Mechanics, John Wil Wiley ey & So Sons, ns, Mechanics, John 1995 Holtz, R.D., Kovacs, W.D., An W.D., An introduction introduction to Geotechnical Engineering, Prentice Hall, N.J., 1981
References Braja M Das, Principal of Geotechnical Engineering, fourth edition, PWS Publishing Company, 1998, Boston Muni Budu, Soil Mechanics and Foundations, Foundations , 2nd edition, John Wiley & Sons, 2007, USA R.F. Craig, Soil Mechanics, Mechanics, (English & terjemahan Prof.Dr.Ir Budi S Supandji) Cernica, J.N., Soil Mechanics, John Wil Wiley ey & So Sons, ns, Mechanics, John 1995 Holtz, R.D., Kovacs, W.D., An W.D., An introduction introduction to Geotechnical Engineering, Prentice Hall, N.J., 1981
Laplace equations The assumptions : Darcy’s law is valid The soil is homogeneous hom ogeneous and saturated The soil and water are imcompressible No volume change occurs
Laplace equation’s of continuity
A
B
Impermeable soil layer Flow x direction
Flow z direction
Water incompressible and no vol. change :
Laplace equation’s of continuity
A
B
Impermeable soil layer Darcy’s law :
Isotrpic soil kx=kz
Simple flow
SF
Flow in Z direction
A1 danA2 are constant;
For flow through layer 1 :
Simple flow
SF
Flow in Z direction
A1 danA2 are constant;
For flow through layer 2 :
From condtion 2:
Simple flow
SF
from
and
Flow of layer 1 = flow of layer2
Simple flow
SF
Example
H1 = 300mm, H2 = 500mm, h1=600mm at z=200mm and h=500mm
Determine h at z=600 mm
Solution
Z=200mm hence
Because z=600mm is located in soil layer 2 hence,
h = 179.9 mm
