Construction World March 2018

STEEL CONSTRUCTION & ROOFING

BRIDGE OVER troubled water

T he Programme seeks to redress past imbalances to historically impoverished communities by implementing infrastructure which will improve the quality of life of these communities. Background Prior to the construction of the bridge, community members crossed the 150-metre-wide Tugela River by removing all clothing and wading across the river with their valuables held over their head in a bucket. The Tugela River is the largest river in the KwaZulu-Natal province with an approximate total length of 502 kilometres from its origin in the Drakensberg Mountains to its confluence with the Indian Ocean. Local community members suffered loss of life, of adults and children, who tried to cross the Tugela River to get to the local road, schools and amenities, but were swept away by the river currents, or attacked by the crocodiles which are often spotted along the river banks. Project team and contract details Hatch Africa was appointed by the client, KZNDoT as the Consulting Engineer to undertake all work stages of the project lifecycle for the proposed bridge, from the outline concepts and feasibility studies, through to the preliminary and detailed design, tendering and procurement of the construction Contractor, and contract administration for the construction of the new structure. The Construction Contract was awarded to Ingonyama Nicon in November 2014. Location of the Works The bridge is located adjacent to the town of Mvumase, at the base of the Maphumulo valley. There was no formalised vehicle access to the site, and no cellphone-signal within a 15 km radius of the site. During construction, this impacted on communication with project team members, suppliers, and transportation of plant and materials. Other site difficulties included unfavourable weather conditions, with summer temperatures exceeding 40˚C, and wet weather which The new Tugela River Pedestrian bridge opened to the public in June 2017 as the first steel pedestrian suspension bridge in the Mvumase, Maphumulo District, in Northern KwaZulu-Natal, South Africa. It is a landmark structure with an overall length of 180 m and towers that are nearly 27 m high, and forms part of the Pedestrian Bridge Programme, initiated by the Client, the KwaZulu-Natal Department of Transport (KZNDoT).

made access to site impossible and prevented construction work from continuing. Nonetheless, despite the numerous challenges, the project was completed in 14 months, within time and budget. The structure An overview explanation of the various elements of the suspension bridge, and load transfer through the elements, is provided below. The load from the bridge deck is transferred to the hangers and then into the main cables, which transfer a part of the load into the towers and a part of the load into the ground through massive anchor blocks. Finally, the load, through the towers and the anchor The new Tugela Bridge project demonstrates commitment from Hatch, and the entire Project Team, to help communities overcome poverty. In undertaking this community project (and similar others), Hatch responded to the need for the private sector to be more engaged in sustainable community development. The project highlights success in the coincidence of commercial and social opportunity and highlights how the best corporate responsibility initiatives can be both scalable and sustainable when they are mainstreamed within the operational activities of a professional services, private sector company like Hatch. The new infrastructure provides hope to the local communities, especially the local children. This is because the Tugela Bridge now provides safe passage to schools, local amenities, such as health care facilities and local supermarkets, and to work opportunities for older community members. Feedback has been received from teachers at the local school expressing how the impressive Tugela Bridge has become a daily source of inspiration to young community members to aspire to careers in Science, Technology, Engineering and Mathematics. Corporate social investment Given the transportation challenges, it was not always possible for the contractor to use the most ideal plant and machinery required to undertake the Works, which resulted in unforeseen health and safety risks due to increased demands for work execution by skilled labour, and potential time-delays. The Engineer and Contractor approached the challenging project with a collaborative attitude, as opposed ttraditional procurement approaches of “pushing risk down the supply chain”. Ongoing, open engagement between the two parties allowed idea-sharing, and risks to be identified and managed economically, quickly and safely. Design Innovation Within Hatch, the culture of innovation is intrinsic to how it blocks, reaches the ground. Social investment

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CONSTRUCTION WORLD MARCH 2018