1. ASSALAMUALAIKUM & GOOD MORNING
DON’T EVER HURT OTHER PEOPLE’S FEELING

2. EARTH RETAINING STRUCTURE
EARTH RETAINING STRUCTURE CAN BE
CLASSIFIED TO 2 TYPES THAT IS:
Externally Stablilized Systems
i) In- Situ Walls
ii) Gravity Walls
B) Internally Stabilized Systems
i) Reinforced Soils
ii) In-Site Reinforcement

3. RETAINING WALL

4. FUNCTION To retain the soil at a slope that is greater than it would
naturally assume, usually at a vertical or near vertical
position.

5. DESIGN The designed retaining wall must be able to
ensure the following :
Overturning doesn’t occur
Sliding doesn’t occur
The soil on which the wall rests mustn’t be overloaded
The material used in construction are not overstressed.

6. DESIGN CONSIDERATION In order to calculate the pressure exerted at
any point on the wall, the following must be
taken in account:
height of water table
nature & type of soil
subsoil water movements
type of wall
material used in the construction of wall

7. The effect of 2 forms of earth pressure need to
be considered during the process of designing
the retaining wall that is:
Active Earth Pressure
“ It is the pressure that at all times are tending
to move or overturn the retaining wall”
Passive Earth Pressure
“It is reactionary pressures that will react in
the form of a resistance to movement of the wall.

8. ACTIVE EARTH PRESSURE It is composed of the earth wedge being retained
together with any hydrostatic pressure caused by
the presence of groundwater.
This pressure can be reduced by:
The use of subsoil drainage behind the wall
Inserting drainage openings called weep holes through the thickness of the stem to enable the water to drain away.

9. PASSIVE EARTH PRESSURE
This pressure build up in front of the toe to resist the movement of the wall if it tries to move forward.
This pressure can be increased by enlarging the depth of the toe or by forming a rib on the underside of the base.

10. GROUNDWATER BEHIND A RETAINING WALL

11. DEFINITION OF GROUNDWATER
Groundwater can be defined as water
which is held temporarily in the soil above
the level of water table.

12. EFFECT OF GROUNDWATER TO RETAINING WALL
have adverse effect to the design and stability
the water behind the wall could increase the
active pressure on the back of the wall
It will reduce the soil shear strength that would
lead to reduction of soil bearing capacity
The water will reduce the frictional resistance
between the base and the soil and also reduce
the possible passive pressure in front of the wall

13. It can be concluded that the existence of
groundwater behind the retaining wall
could lead to failure of retaining wall.
Therefore, ways must be found to drain the
groundwater out from behind the wall.
Normally, weep hole will be installed in the
retaining wall where it will penetrate the
retaining wall and drain the area
immediately behind the wall.

14. Adequate spacing between the weepholes
allow uniform drainage from behind the
wall.
Weep holes should have filter material
between the wall and the backfill to prevent
fines migration, weephole clogging, loss of
backfill and caving

15. EARTH RETAINING STRUCTURE SPECIFICALLY ON “GRAVITY WALL”

16. GRAVITY WALL There are many types of gravity wall such as
the followings:
Massive Gravity Wall
Crib Wall
Cantilever Gravity Wall

17. GRAVITY WALL

18. It’s construction only need simple materials
and moderately skilled labor
But the required volume of material is very
large because there’s steel reinforcement is
used.
Eventhough it need moderately skilled
labor but the construction process is very
labor extensive.

19. MASSIVE GRAVITY WALL Often made of mortared stones, masonry or
reinforced concrete
It resist the lateral forces from the backfill
by virtue of their large mass
These walls are very thick, so the flexural
stresses are minimal and no reinforcement
is needed.

20. CRIB WALL Another type of gravity retaining structure
It consists of precast concrete members linked together to form a crib
The zone between the member is filled with compacted soil

21. CRIB WALL

22. CANTILEVER GRAVITY WALL
STEM
8 IN WIDE
CONCRETE
BLOCKS
SOIL
REINFORCING
STEEL
12 IN. WIDE
CONCRETE
BLOCK
Large Flexural Stresses
At Base Of Stem
REINFORCED
CONCRETE FOOTING
TOE
HEEL

23. CANTILEVER GRAVITY WALL
It is a refinement of the massive gravity wall
concept
These wall have much thinner stem and utilize
the weight of the backfill soil to provide most
of the resistance to sliding and overturning
These walls require much less construction
material because the crossection of this wall is
much smaller.

24. It have a large flexural stresses which
requires the use of reinforced concrete or
reinforced masonry
It must be carefully constructed & requires
skillful labor
less expensive than mass gravity walls
most common type of earth retaining
structure.

25. COUNTERFORT WALL

26. GABION WALL

27. EARTH RETAINING STRUCTURE SPECIFICALLY ON “IN-SITU WALL”

28. IN-SITU WALL Different from gravity walls
There are many types of In-Situ wall such
as the followings:
a) Sheet Pile Walls
b) Soldier Pile Walls
c) Slurry Pile Walls

29. SHEET PILE WALLS Sheet piles are tine, wide steel piles
Driven to the ground using pile hammer
Series of sheet piles in a row form a sheet pile wall
It’s usually necessary to provide lateral
support at 1 or more levels above the
ground that can be done using 2 ways that
is internal braces or tieback anchor

30. Tieback Anchors are tension members
drilled into the ground behind the wall
The most common type is a grouted anchor
with a steel tendon

31. Wall With Tieback Anchors
WALER
GROUTED TIEBACK
ANCHOR
SHEET PILE WALL
SOIL
Wall With Tieback Anchors

32. SHEET PILES

33. SHEET PILE WALLS

34. SOLDIER PILE WALLS Consist of a vertical wide flange stell
members with horizontal timber lagging.
Often used as temporary retaining structures for construction excavation

35. SOLDIER PILE WALL

36. SLURRY WALLS It’s a cast-in-place concrete walls built using
bentonite slurry
The contractor digs a trench along the proposed
wall alignment and keeps it opem using the slurry
The reinforcing steel is inserted and the concrete
is placed using pumps / tremie pipe
As the concrete fills the trench, slurry exits at the
ground surface.

37. SLURRY WALL

38. SLURRY WALL

39. HOPEFULLY YOU UNDERSTAND THIS CHAPTER
SYUKRAN JAZILAN = DOMO ARIGATO GOZAIMASU