Construction World January 2018

Project information • Consulting engineer: Royal HaskoningDHV in JV with Henwood and Nxumalo • Client: eThekwini Transport Authority and KZN Department of Transport • Contractor: Group Five P577 Joint Venture; Umsimbiti Civils (JV Partner)

under Contract ZNT 2247T until the design was amended to include the BRT lanes. Longitudinal drainage was incorporated where cross drainage was not possible due to clashes with barrier or retaining wall footings. Time pressure to quantify the addition of the BRT lanes, to compile a document and to negotiate rates was immense. Aesthetics of engineering elements Aesthetics in any design process does not happen by accident. Care needs to be taken in major engineering projects during the design process and, perhaps most difficult – given the time and cost implications – attention to detail in the construction phase. In the case of Main Road 577 the construction is complemented by the natural characteristics of a steep rugged valley. The curvilinear nature of the alignment returns the favour and the road takes on the appearance of an alpine highway. In as far as possible, the treatment of the rock face was planned to match the appearance of natural rock and gabions were used where possible instead of concrete to preserve a natural appearance. The pedestrian bridges were designed to emphasise the identity of the MR577 corridor. The pattern on the bridge deck was chosen from an architectural competition and the bridges were built by emerging contractors, mentored through the training programme. The final result is easily seen and appreciated by anyone who drives the road and it is likely that the traveller will enjoy the journey more because of the obvious challenges that faced the engineers. →

Erection of reinforced earth walls in progress.

which was anchored back into the cut slope, incorporating guard- rail structures in selected places to increase the height of the interceptor walls. Slope Stabilisation Design The anticipated rockbolts or anchor spacing and lengths stabilising the interceptor gabion wall structure and the cut through the underlying fill were detailed. Management of planning and technical design The original design catered for an initial two lanes in each direction, but with an allowance for one lane in each direction to be added in the median in the future. The BRT lanes were incorporated into the median but the requirement was for them to be incorporated adjacent to each other without a median separation. The contractor was asked to delay their drainage installation

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CONSTRUCTION WORLD JANUARY 2018