River Roach, Littleborough
River Roach, Littleborough
- CLIENT : The Environment Agency
- CONTRACTORS : C T Construction Ltd
REQUIREMENT
The project consisted of removing a 100m section of failed existing retaining wall, along a stretch of the River Roach, re-grading the slope and using a mechanical ground anchor system to stabilize the embankment.
To determine the appropriate anchor size and depth of installation for design load requirement, on-site testing was carried out by Anchor Systems (International) Ltd to determine the actual holding capacity within the substrate.
SOLUTION
The final solution called for a life expectancy on the components of 20 years, therefore a fully galvanised system was selected.
The tests determined that the mechanical ground anchor, driven to 6m best suited the requirement with sufficient safety on both the system and substrates.
Three rows of anchors at 1.2m spacing were used on the slope which varied between 45 and 60 degrees. Due to site constraints both machine mounted breakers and held hammers where used for installation.
The anchors used, stabilized the embankment as well as secured a geotextile membrane and Reno mattress, which was used to prevent the topsoil from being washed out in high water.
A seeded membrane was then embedded into the Reno mattress to allow for a vegetation covering.
