The gravity retaining wall is often larger because the soil pressure is greater than the gravity load.
The weight acts as a counterbalance to atmospheric pressure.
Considering sliding, overturning, and bearing pressures are necessary while designing this type of retaining wall structure.
Numerous materials such as brick, stone, and concrete, can be used to build it.
It is available up to 3 meters in height.
Gabions, bin retaining walls, and crib retaining walls are examples of gravity retaining walls.
How To Build a Gravity-Retaining Wall?
Step 1: Site Preparation and Excavation:
Get rid of any organic soil and surface vegetation.
Excavate a base trench at least 12 inches (300 mm) deep and 24 inches (610 mm) wide as per the official plan.
Substitute compactable material for unsuitable soils.
The buried block must be at least 6 inches (150 mm).
Starting at the lowest level, work your way up the retaining wall.
A stepped foundation is required for walls built on slopes.
Dig a level trench in the slope starting at the lowest point until it is deep enough to hold the base material and one full block.
At this point raise a block and start digging a new base trench section.
Go up as necessary until you reach the top of the ramp.
Always supply one full unit or more at each step.
Step 2: Install the base material:
Place the wall rock in the base trench to a depth of at least 6 inches (150 mm), compact it and level it according to the official drawings.
According to the engineer, the soil on the ground must form a proper foundation.
Step 3: Install the base course:
Start with the lowest retaining wall height.
Set retaining wall blocks on the base material in the centre of the trench.
Each unit must be level and aligned and this must be adjusted.
A drain pipe is required to maintain walls that are taller than 4 feet (1.2 m) or built on silt or clay soils.
For location and details, see the approved plan.
On separate drain placements, consult design specifications.
Step 4: Install backfill material and wall rock:
Wall rock shall be placed at least 12 inches (300 mm) inside the hollow core and behind the gravity retaining wall.
Backfill the front of the base course and behind the wall rock with suitable soil.
The space behind the block should be compacted using a plate compactor.
Compact in lift no more than 8 inches (200 mm).
Step 5: Install additional courses:
Remove all excess material from the top surface of the retaining wall blocks.
This can be accomplished by sliding the block into place and dropping in subsequent blocks.
Vertical seams on the series of blocks below should be at least 3 inches away from the blocks below them (75 mm or one-fourth the length of the block).
As the retaining wall is constructed, check and make adjustments for level, alignment, and wall batter.
Wall rock should extend at least 12 inches into the block core and behind each block (300 mm).
Fill the space behind the wall rock using acceptable soil.
Use plate compactors Course 2 and above to directly compact the space behind the blocks and the area above the blocks.
Compact in lift no more than 8 inches (200 mm).
Obtain the required height for the retaining wall.
To finish the wall, fill 8 to 12 inches (200 to 300 mm) of low permeability at the last lift.
Analysis of Gravity Retaining Wall:
Before you assess any retaining walls, be certain that you have a clear image of the job site’s conditions.
Each retaining wall must be constructed in such a way that it can handle the weight of the soil behind it as well as other loads on it.
In a normal gravity wall analysis, sliding, bearing, and overturning forces are taken into account.
A worldwide stability check will also be required for sloped or overloaded locations.
Sliding:
The ability of a wall structure to resist horizontal forces acting on the wall during sliding.
The safety factor is 1.5.
Retaining Wall Overturning:
The structural ability of a retaining wall to resist the overturning moment introduced by rotational forces acting on the wall.
The safety factor is 1.5.
Bearing Capacity:
The soil’s capacity to support the weight of the retaining wall structure.
The security factor is 2.0.
Global stability:
Internal strength is the ability of soil to support the entire soil mass.
For help evaluating your site, contact a local design expert.
Other Aspects:
- Slope.
- Surcharge.
- Terrace.
FAQ: What is Gravity Retaining Wall?
Q1. Is a gravity retaining wall flexible or rigid?
Typically, gravity-type structures are “stiff,” while non-gravity-type structures are “flexible.”
Q2. What constitutes a gravity retaining wall’s essential components?
Gravity retaining walls withstand lateral ground forces by using their own weight as support.
Seismic loads, lateral ground pressure pressing on the rear face, and vertical pressures resulting from the weight of the wall operate as the main forces on gravity retaining walls.
Q3. Which retaining wall breakdown occurs the most frequently?
The main reason retaining walls fail is inadequate drainage.
The hydrostatic pressure that builds up behind a wall can push on it and cause it to bend out or crumble if too much water is absorbed into the soil.
Conclusion:
An effective retaining wall can stabilize the soil and prevent the structure from overturning and sliding.
A proper gravity retaining wall can also reduce building costs.
Section Under: Retaining Walls
