When managing sloped landscapes or preventing soil erosion, retaining walls play a vital role in functionality and aesthetics.
No matter, if you’re planning a garden redesign, addressing an incline in your yard, or undertaking a commercial project, understand the different types of retaining walls.
In this post, we’ll explore the three main types of retaining walls—gravity, cantilevered, and anchored—and how each serves a unique purpose.
Three Types of Retaining Walls
1. Gravity Retaining Walls
Gravity retaining walls rely on their mass to resist the pressure of the soil behind them. These walls are typically constructed from heavy materials like stone, concrete, or brick. These are the one of the cheapest retaining walls.
The sheer weight of the wall itself provides stability and keeps the soil in place. Due to their simple design, gravity walls are often used for shorter walls, though they can be built higher by increasing their base width.
Their thickness makes them quite strong, but they require a large footprint to work effectively.
These retaining walls often incorporate drainage solutions to further stabilize the structure and prevent hydrostatic pressure build-up behind the wall.
Common drainage options include using free-draining backfill materials such as gravel, installing perforated drainage pipes, and incorporating weep holes at the base of the wall.
These measures allow water to escape from behind the wall, reducing the risk of structural failure due to water logging.
Despite their many advantages, certain limitations must be acknowledged. The large footprint required by gravity retaining walls can be a significant constraint in areas where space is at a premium.
The need for a substantial base to ensure stability means that these walls may not be suitable for tight urban environments.
Moreover, their construction can be labor-intensive and time-consuming, particularly when natural stone or brick is used.
2. Cantilevered Retaining Walls
Cantilevered retaining walls are designed using reinforced concrete or masonry. They consist of a thin stem and a base slab, with a section of the base extending beneath the backfill material.
This shape creates a lever arm (cantilever) that helps the wall resist the lateral pressure of the soil. Cantilevered walls are more efficient in material use than gravity walls, making them ideal for taller or more substantial retaining structures.
They also take up less space and are commonly used in commercial or large-scale residential projects.
One of their primary benefits is structural efficiency, as they require less material than gravity walls to achieve the same level of stability.
This efficiency is due to their design, which utilizes a thin vertical stem and a base slab with a heel that extends back under the soil.
These walls are engineered to optimize space—unlike gravity walls that rely on their massive bulk to hold back soil, cantilevered structures maximize usable space, making them ideal for urban and commercial settings where space is at a premium.
Additionally, cantilevered retaining walls can be tailored to heights exceeding those of typical gravity walls, which makes them suitable for projects requiring substantial elevation changes.
Often, these walls are accompanied by counterforts—vertical braces attached to the backside at regular intervals—to further fortify the structure against lateral forces, thus ensuring long-term stability and durability in demanding conditions.
3. Anchored Retaining Walls
Anchored retaining walls are used when extra reinforcement is needed. These walls are supported by anchors or tiebacks driven into the ground behind the wall.
The anchors provide additional resistance against the pressure of the soil, allowing the wall to be thinner while still being able to withstand significant force.
This method is particularly useful for very tall retaining walls or situations where space is limited but strength is crucial. Anchored walls are often used in mountainous areas or locations with steep slopes.
These walls are especially valuable when constructing in environments where traditional retaining walls would be impractical or impossible to use due to space constraints or extreme height requirements.
For instance, in urban settings where buildings are erected closely together, the use of anchored walls prevents the need for excessively thick walls, thus conserving valuable space while still maintaining robustness.
Moreover, they are indispensable in mountainous regions, managing the high soil pressure from steep slopes and preventing landslides, thus ensuring the safety and durability of transport routes and residential areas.
Final Thoughts
Gravity walls depend on weight, cantilevered walls use a concrete structure, and anchored walls employ added reinforcement for strength. Each type has its specific advantages and applications
