Wall Profile 1
Flat ground in front of and behind wall
1/ Simple low risk retaining wall.
Wall Profile 1A
Flat ground in front of and behind wall
With Building or Vehicle Surcharge
1/ Increased loads on wall.
2/ Stronger wall required than Profile 1.
Wall Profile 2
Sloping ground in front of wall and flat ground ground behind wall
1/ Reduced soil at base of wall to resist sliding.
2/ Foundation and toe depth needs to be increased over Profile 1 wall.
Wall Profile 2A
Sloping ground in front of wall and flat ground behind wall
With Building or Vehicle Surcharge
1/ Reduced soil at base of wall to resist sliding
2/ Increased loads on wall.
3/ Stronger wall required than Profile 2.
4/ Foundation and toe depth needs to be increased over Profile 2 wall.
Wall Profile 3
Flat ground in front of wall, sloping behind wall
1/ Additional load from the blue wedge of soil.
2/ Stronger wall than Profile 1 required to resist added load.
3/ Foundation and toe depth needs to be increased over Profile 1 wall.
Wall Profile 3A
Flat ground in front of wall, fill with steep batter behind wall
1/ Owner tries to avoid building consents, but often fails to increase the strength of wall, resulting in failure of the retaining wall!!!
2/ Additional load from the blue wedge of soil.
3/ Retaining wall size needs to be increased to resist added load.
4/ Some local building regulations define the height, as the distance from the base, to the top of the retained soil.
5/ Professional engineers are unlikely to approve this design of wall.
Wall Profile 4
Sloping ground in front of wall, sloping behind wall
1/ Additional load from the blue wedge of soil.
2/ Reduced soil at base of wall to resist sliding
3/ Increased loads on wall.
4/ Stronger wall required than Profile 2.
5/ Foundation and toe depth needs to be increased over Profile 2 wall.
Wall Profile 5
Terraced Walls
1/ Complicated high risk retaining walls.
2/ Lower wall subjected to extreme loads from upper wall
3/ Lower wall needs to be designed to take the added loads from the upper wall
4/ The retaining walls are deemed related unless distance between the back of the lower wall and the
front of the upper wall is at least twice the height of the taller of the two walls.
5/ The height for building regulations of related retaining walls, is normally the height from the base of the bottom wall to the top of the upper most wall.
6/ Professional engineers site inspection and designs are almost always required for related, terraced walls.
No liability is accepted where a
typical profile is used as a the basis for the final design.
The details provided are guidelines only.
For advice or assistance with the design of an economical gabion retaining walls, please email engineer@gabion1.co.nz