Construction World December 2018

component of the upgrades. Cut widenings in the 5 km long pass were needed in order to flatten out certain of the sharp bends, as well as to make provision for an additional lane and two arrestor beds. There were eight major cuttings within the pass, with heights of up to 40 metres and cut slopes as steep as 75 degrees. In order to protect the future road users against falling rocks, various slope stabilisation methods were used. Soil nail anchors with mesh draping is being provided along the higher quarzitic sandstone cut faces, while tied back 8-10 metre high gabion walls are provided in the weathered dolerite sections. Rock traps of 4-6 metre wide and concrete barrier walls are provided at the foot of the cuttings. The blasted material from the cuttings was carted to the onsite crushing facility that was established in order to produce crushed stone material for use in the road layerworks, including a new crushed stone base and the bituminous double seal surface. Safety improvements at the Doornkop Village, which included the construction of a 3 km pedestrian sidewalk facility separated from the National Road including access management by means of upgrading the internal village access roads formed part of the project. Community Participation objectives for the project, which included targeted labour and targeted enterprises was set at 18%. The actual expenditure was 32,6% or R112-million of the total project cost of R350-million. The project was completed in December 2017 and opened to traffic in time for the school holidays. 

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PROJECT INFORMATION

• Company entering: HHO Consulting Engineers • Client: SANRAL • Project value: R403-million • Start date: April 2010 • End date: December 2017 • Main Contractor: KPMM Roads & Earthworks • Project Manager: SANRAL • Consulting Engineer: HHO Consulting Engineer