1. WATER IN SOIL NOR KHAIRIAH BINTI KARIM (A17KA0123)
NORAZIZAH BINTI JOHAN (A17KA0127)
NUR ADLINA BINTI AZAHARI (A17KA0131)
NUR AYUNNI NABILA BINTI KAMALLUDDIN (A17KA0135)
NUR HARSYIKIN BINTI BADRI (A17KA0139)
NUR NAZURAH BINTI ABDUL RAZAK (A17KA0143)
NUR SYAZWANI BINTI KAMARUZAMAN (A17KA0146)
NURADIBAH BINTI HASHIM (A17KA0150)
NURLIYANA BINTI MOHD NORHADI SHAH (A17KA0153)
NURSYASYA BINTI ZULKEPLI (A17KA0157)
NURUL ALIAH BINTI YUSOFF (A17KA0161)

2. DARCY LAW (saturated flow)
Has internal
pore pressure
Above water table
Pull of gravity downward
VADOSE
GRAVITATIONAL
Attraction water-water
1.Gravel : Big Particles – lots of
space – water move quickly
COHESION
Saturated
(water + soil)
ZONE
PHREUTIC
2.Sand : Small spaces between particles – water move slowly
ADHESION
FORCES
Below water
table
Attraction water-soil
3.Silt : Spaces between particles
even smaller – water move
slowly through
CAPILLARY
WATER IN SOIL
Taken up by plants
DARCY LAW (saturated flow)
4.Clay : Barely any space between
particles – water can take 100’s
years to move through
v α ί
v = kί
BERNOULLI EQUATION
ℎ 𝑡 = ℎ 𝑧 + 𝑢 𝛾 𝑤 + 𝑣 2 2𝑔 = ℎ 𝑧 + ℎ 𝑝
PERMEABILITY
Borehole
Shape of
soil particle
Methods
*To show – water could flow
through soil medium
Fields
Pumping
Porosity soil
Factors
Laboratory
Tracer Test
Viscocity
Degree saturation
of air
Falling head test
(Fine soil)
Constant head
test (Coarse soil)
Particle size

3. Total stress, σ Pore water pressure, u Effective stress, σ ′ σ = 𝛾.𝑧
Calculation from flow net :
q = 𝑘𝐻 𝑁 𝑓 𝑁 𝑑
𝑁 𝑓 = no. of flows
k = permeability value
𝑁 𝑑 = no. of drop
Total stress, σ
σ = 𝛾.𝑧
σ increases with depth and unit weight
Pore water pressure, u
SOIL STRESS
SEEPAGE
u = 𝛾 𝑤 . ℎ 𝑤
Below water table : u (+ve)
Dry soil : u = 0
Above water table (saturated soil) : u (-ve)
Effective stress, σ ′
σ ′ = σ - u
Potential drop :
∆𝑞=𝑘 𝐻 𝑁 𝑑
H = head difference between upstream and downstream sides
𝑁 𝑑 = no. of drop
Saturated soil
Not influenced by water pressure, u