This project started as a conventional Permacrib gravity wall to retain a cutting formed in sloping ground to provide an access road into the new Superstore. However an attractive group of trees grew on a selection of the slope on the line of the proposed wall.

Conventional gravity wall construction of the 6 metre high walls would have required excavation and disturbance of the trees root systems and threatened their immediate stability and long term survival.

The client wanted to save the trees and also to keep the natural appearance of the Permacrib timber walling system.

Solution:
The face itself was temporarily stabilised using soil nails, meshing and fin drains while the excavation proceeded and permanent stability of the soil nailed design was provided using a reinforced concrete slab faced off with Permacrib which also acted as the permanent shutter to the R.C. slab. This technique reduced the depth of excavation required over the area of the trees by over 2.5 metres avoiding serious disturbance to the root systems.