Decorton (Pty) Ltd, Cape Town based retaining wall contractor specializing in Terraforce earth retaining products, was appointed sub-contractor for all retaining walls during extensive up-grade work at L’Ormarins, a prestigious wine estate in the Western Cape area. The end result is a very pleasing noisebarrier, and blends in nicely with the surrounding environment.
A massive, semi-circular wall of a maximum height of 9.5m was built around the new underground cellar. Up to a height of 4m the engineer specified a double layer of L11 Terraforce blocks, filled with reinforced concrete on a reinforced foundation. In addition these blocks were tied back to the cellar walls with geofabrics every second row.
Above that level a single skin of L11 blocks filled with topsoil – also tied back every second row – was used. A unique feature is an invisible air vent incorporated into the wall by way of L11 blocks, unfilled to allow unhindered passage of exhaust air generated in the cellar.
The underground restrooms of the cellar are conventional concrete and brick structures made waterproof with Derbygum torch-on membranes under a Zipcor (Kaytec) drainage and protective layer.
Further subsoil drainage has been provided at foundation level of both the building and the surrounding Terraforce L11 retaining wall with layers of reinforcing grid provided to lend additional stability to the substantial height of backfill around and above the building.
Elsewhere on the site, L11 blocks were used extensively for toe-walls alongside a steep new access road, for various retaining walls and for a convex landscaping feature.
In line with the growing trend to specify water wise indigenous plants, these were used here to round off and soften this substantial installation.