Retaining walls are structures used to retain soil or rock in a vertical position. Common materials used include wood, steel, concrete, and gabions. Retaining walls are classified as externally or internally stabilized. Externally stabilized include in-situ and gravity walls. Internally stabilized include reinforced soils and in-site reinforcement. Design considerations include ensuring stability against overturning, sliding, and overloading soils. Design also accounts for active and passive earth pressures. Common gravity wall types are massive gravity, crib, and cantilever walls. In-situ walls include sheet pile, soldier pile, and slurry walls. Reinforced and geosynthetic retaining walls are advanced wall types.

1. RETAINING WALL

2. Retaining wall:
Retaining walls are structure used to retain soil, rock or other materials in a vertical
condition.
Hence they provide a lateral support to vertical slopes of soil that would otherwise collapse
into a more natural shape.
Most common materials used for retaining walls are:
- Wood sheets;
- Steel and plastic interlocking sheets;
- Reinforced concrete sheets;
- Precast concrete elements (crib walls and block walls);
- Closely spaced in-situ soil-cement piles;
-- Wire-mesh boxes (gabions);
- Anchors into the soil or rock mass (soil nailing).

3. EARTH RETAINING STRUCTURE
Earth retaining structure can be classified to 2 types:
A) Externally Stabilized Systems
i) In- Situ Walls
ii) Gravity Walls
B) Internally Stabilized Systems
i) Reinforced Soils
ii) In-Site Reinforcement

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:
a) Active Earth Pressure
“ It is the pressure that at all times are tending
to move or overturn the retaining wall”
a) 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:
i) The use of subsoil drainage behind the wall
ii) 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. GRAVITY WALL
There are many types of gravity wall such as
the followings:
a) Massive Gravity Wall
b) Crib Wall
c) Cantilever Gravity Wall

11. GRAVITY WALL

12. cement mortar
plain concrete or
stone masonry
cobbles
They rely on their self weight to
support the backfill
12

13.  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.
 Even though it need moderately skilled
labor but the construction process is very
labor extensive.

14. 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.

15. 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

16. CRIB WALL

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

18. 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 cross
section of this wall is much smaller.
 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.

19. Reinforced;
smaller section
than gravity
walls
They act like vertical
cantilever, fixed to the ground
19

20. COUNTERFORT WALL

21. GABION WALL

22. 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

23. 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.
 Tieback Anchors are tension members drilled into the ground behind the
wall
 The most common type is a grouted anchor with a steel tendon.

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

25. SHEET PILES

26. SHEET PILE WALLS

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

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

31. Basha
Retaining Walls - Applications
Metros and Subways
Road
Train
31

32. Basha
Retaining Walls - Applications
highway
32

33. Basha
Retaining Walls - Applications
High-rise building
basement wall
33

34. Advances in retaining wall
Reinforced Retaining Walls
• Sometimes the complexity or wall height required for certain
installations require retaining walls that are reinforced by either
geofabric material or, in really tough cases, concrete filled doubleskin
layers of blocks

35. Geosynthetic Reinforced Soil
Segmental Retaining Walls
• Geosynthetic reinforced soil segmental retaining
walls utilize reinforcing sheets of geogrid or
suitable woven geotextile which are attached to the
fascia and are embedded in a body of engineered
fill.
• The integrated nature of the fascia and the abutting
large body of reinforced soil thereby supports the
applied earth forces. In this case the 'gravity'
component of the retaining wall is provided by the
reinforced soil mass acting as a monolithic unit.