Lateral Earth Pressures

Question 1

What is lateral earth pressure?

Answer 1

Is the force exerted the by the soil mass on earth retaining structure

Question 2

What are the factors that affect lateral earth pressure?

Answer 2

Shear strength
Inclination of the surface of the backfill
Height and inclination of the retaining wall
The nature of wall movement under lateral pressure

Question 3

At rest earth pressure
Active earth pressure
Passive earth pressure

Answer 3

At rest… is when the retaining wall stand vertically

Active…. Is when the retaining structure is being pushed away from the backfill due to external forces

Passive… is when the retaining structure pushes the soil mass

Question 4

Rankine’s theory assumptions

Answer 4

-The soil mass is semi-infinite,homogeneous
-The ground surface is a plane which may be horizontal or inclined
-the back of the wall is vertical
-the back of the wall is smooth

Question 5

Coulomb’s theory

Answer 5

-The backfill is homogeneous, isotropic and elatically undeformable by breakable
-allows the back of the wall to be inclined
Friction along the soil-wall interface
The slip surface is plane which passes through the heel of the wall

Question 6

Types of retaining walls

Answer 6

Gravity retaining wall
Cantilever rw
Sheet pile wall

Question 7

Suitability of deep foundations over shallow foundations

Answer 7

Poor soil conditions at shallow depths, thus deep foundations can transfer lods to stronger soil at greater depths

High structural loads,.. deep foundations can provide mecessary support by reaching deeper to more stable soil strata