Welcome back from a well deserved year end break. I am certain the New Year will bring with it hard work as well as success for us all. Let’s not let the past two years pull us down, but rather rise to the challenge and make every business transaction count towards a better and brighter future for us all.
Louis Cheyne
THE HIGH RETAINING WALLS
This above example is of a well-constructed wall built for a distribution centre in Pretoria.
This wall has a height of 5m and a total length of 105m.
This work was undertaken by about 14 people together with a bankhoe loader to help load rock from the stockpile directly into the baskets.
The typical work rate is one man per cubic meter per day.
In this case, however, the man and machine combination increased the daily rate to approximately 1.5m3 to 2.0 m3.
A total quantity of 540m3 of gabion walling was installed.
The gabion facing was rotated into the embankment with a four-degree batter slope to further enhance the walls stability, with the base founded to a depth of 0.5m base width was 1.5m for the first two gabion levels with subsequent layers of 1mx1m
SABIE PROJECT
This gabion wall performs both an erosion control and retaining function for a road project near Sabie in Mpumalanga. Four walls were installed with various lengths. The first retaining wall is 4 m high and was used to retain the cut-slope embankment, reduce water velocities off the tailings slope and act as a rock catch wall.
The second gabion wall below the roadway (halfway up the fill slope) is designed to prevent lateral movement of soils.
This reduces the risk of roadway settlement and failure.
TYPES OF RETAINING WALLS
Did you know that there are various types of retaining walls for specific requirements – lets have a look at what these are:
MASS-GRAVITY GABION RETAINING WALL (DRY)
MASS-GRAVITY GABION RETAINING WALL (WET)
This structure is typically founded in a river.
A flexible river mattress apron is required to prevent scour at the toe of the gabion wall, especially if the structure is founded on soft river sand.
SKIN REVETMENT GABION WALL
This wall is used where the embankment stability is safe. This wall type is used to prevent shallow-slope failures, plus rock falling out of the slope.
GABION MASS-GRAVITY CATCH WALL
This option is designed to catch rocks or soil falling out of the embankment.
GABION VERTICAL-FACED MASS-GRAVITY WALL
A vertical-faced gabion retaining wall is used in an area where limited spacing is available.
TERRACED GABION WALL
Popular for playgrounds and sports fields, a small terrace can be erected using garden gabions to make the slope of the land flatter.