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How Stonebloc Gravity Walls Work

Engineering Basics

Before we dive into what a gravity wall is and how it could work for you, you'll need to understand a couple of engineering basics. 

Stonebloc is primarily a gravity- based retaining wall system. A gravity wall system relies on the combined weight of the blocks to resist overturning forces. 

Every wall with a load pushing against it supports a “wedge” shaped load. The wedge is defined as the area which extends beyond the failure plane of the material type present at the wall site and can be calculated once the friction angle is known.

Gravity Wall Wedge
(Wedge-shaped load that pushes against a gravity wall)

All walls need to withstand four key forces:



Ability of the retaining wall structure to overcome the horizontal force applied to the wall.



Ability of the wall structure to overcome the overturning moment created by the rotational forces applied to the wall.

Bearing Capacity

Bearing Capacity

Ability of the underlying soil/foundation to support the weight of the wall structure.

Global Stability

Global Stability

Ability of the internal strength of the material to support the complete material mass.


How the Stonebloc Gravity Wall Works

Stonebloc gravity retaining walls work with a combination of interlocking shear keys and the weight of concrete.

The shear keys that are located at the top of Stonebloc blocks work to resist sliding and lateral soil pressure. The shear key does not reduce the impact of overturning. This is rectified by the weight of the blocks themselves - the rotation point at the bottom of the block helps to push the block back to its original position.

Relying on gravity and shear keying in two horizontal planes it achieves its strength as either a standalone gravity wall or a retaining wall able to withstand high surcharge levels.

One of the most common structures for our Stonebloc gravity retaining wall has a mixture of block types. These blocks are a 1200 base, an 800 base, 800 standard block(s), and a 200 Capper block.


Annotation of a Stonebloc Wall
(Annotated picture of a Stonebloc wall in situ pointing out the different block types)

The benefits of Stonebloc’s gravity wall

By choosing Stonebloc, you'll get access to a unique combination of benefits. Some of these include:

  • Easy to install
  • Fast installation
  • Can reach a height of 2.4m
  • Various kPa’s: 0 kPa, 5kPa, 12kPa
  • Resists sliding and overturning
  • Can be adapted to suit many projects and situations

Common instances of a gravity wall

Stonebloc’s retaining walls are most often seen in residential developments. The flexibility of the system, however, does mean that you are limited to one

Here are some Stonebloc case studies:

You can also use Stonebloc gravity walls for low landscaping walls and slope rehabilitation.

Stonebloc Landscape Wall
(Stonebloc's Low Landscape Wall)

If you’re wanting retaining walls that can withstand heavier loads, you may be interested in Stonebloc’s Reinforced Earth Walls.

Build your own Stonebloc Gravity Wall today!

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