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Counterfort retaining walls are similar to cantilever walls except they have thin vertical

concrete webs at regular intervals along the backside of the wall. These webs are knownas counterforts.Triangular-shaped counterforts are added to the rear of abutment wall slab

to provide further flexural rigidity and resist the lateral earth pressures by the depth ofbackfill material.

Counterfort retaining walls:

The counterforts tie the slab and base together, and the purpose of them is to

reduce the shear forces and bending moments imposed on the wall by the soil. A

secondary effect is to increase the weight of the wall from the added concrete.

Can be precast or formed on site.

Counterfort retaining walls are more economical than cantilever walls for heights

above 25 ft.

Buttressed Retaining Walls

A buttressed retaining wall is basically identical to a counterfort wall except for onething. The support wall is on the outside of the retaining wall. They are visible. The

buttresses add incredible strength to the wall system. For the retaining wall to fail or tip

over, the buttresses would have to be crushed. The buttress concept was widely used inthe construction of many cathedrals in Europe.

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Because of the height of the cathedral walls, the buttresses helped to stabilize them. They

do the exact same thing in a retaining wall. Once again, if you intend to build one of these

walls, you must give serious consideration to hiring an engineer. Situations whichdemand this type of wall usually have tremendous loads which bear against the walls.

The buttresses can often be designed to be decorative in nature and covered with stone or

some other material. Depending upon the overall length of the wall, you may haveseveral buttresses. They can be spaced to create rooms, parking spaces, handball courts or

any other functional space.