In April 2007, we were appointed by Steffanutti Bressan in Kempton Park as the supplier for the gabions and geotextiles for the site near Steelpoort in Limpopo for the client Asa Metals (Pty) Ltd. Our gabion prices were the best and at the time we were asked to assist the consulting engineer in Midrand with the gabion sectional and layout drawings.
The quantity estimated was approximately 6000m³ and mass-gravity gabion retaining walls ranging in size from 2m to 8m height were designed, foundation depth about 10% of the height and base width about 50-60% of height, determined by the soil parameters on site. A B.O.Q. was done for the works to determine precise volumes and sizes required to start the installations.
All gabion materials supplied were class A galvanised as per SANS 1580 specification with A4/U24 – 210g/m², non-woven, Bidim geotextile, laid at all gabion and soil contact faces.
We also provided a skilled gabion contractor to provide an estimate for the labour only component of the installations, together with planned on-site plant required- and time completion estimates. He was, however not used due to the existing prices tendered on the works were lower than his submissions.
If all goes to plan, the project will be completed by the end of August 2008. We visited the site a few times to advise on the correct installations and provide any other advice necessary to complete the project on time and with the required neatness/quality. Production achieved on this one was about 2.5m³ per man per day, normally contractors allow for one man per m³ per day.