Construction World February 2017

PROJECT PROFILE

→ A structurally sound solution came in the design of a hanging shutter. The critical load combination for the structure happens when the water is at its lowest point. The shutter has been designed to function normally without the need for water pressure on the rear face of the unit. The forces acting on each pedestal connection on the anchor piles amounted to 665 KN, requiring the web of the anchor pile to be stiffened with gussets to prevent buckling. Horizontal forces which tended to ‘push’ the shutter off the steel piles during casting were mitigated by pre-welding a cleat to the king pile prior to driving. The specification for cope beam structures to be cast in the dry, called for clever construction technique in the use of a de-watered shuttering system. Each and every pour requires the design and construction of a new seal to overcome water and tidal challenges. A double skin was used to trap water that seeped in which was then channeled to a sump for dewatering. Divers are required to tighten and align the shutter at its base, and then the pour must be perfectly timed to coincide with the low tide. This means a fleet of ready-mix trucks on site, ready to discharge in order to stay ahead of the tide as it rises. Stripping of the shutter was only allowed once the concrete had achieved a minimum of 35 MPa as the concrete element formed a cantilever and needed to be able to support its own weight. Once the concrete was cast and the shutter stripped, a second above tidal level cast was undertaken to bring the quay up to its final level. Corporate social investment Ports all over Africa are experiencing high cargo volumes, calling for greater capacity to safely accommodate bigger sized ships. As South Africa’s principal container port generating more than 60% of revenue, the Maydon Wharf infrastructure upgrade will result in much needed increased capacity for the country’s economic functioning and growth, and will alleviate the congestion currently experienced in the port. The SSA JV team is proud to have been part and parcel in delivering a key development project for the client and ultimately, the contribution to society, it will make in employment opportunities in Durban. Throughout the project duration, the drive for education and continuous learning has remained resolute, even with the economic downturn experienced in the construction industry. Graduates from the Go for Gold education to employment initiative have undergone experiential training and continue to be part of the

SSA JV team, providing them with the necessary skills and mentoring for their professional development. The project has employed a significant number people locally, and takes pride in its commitment towards training and mentorship, encouraging individuals to increase their skills set and gain promotion. In 2014, the SSA JV team were the main contributors towards the Jirah academy, a community based satellite campus, which is now offering N1 to N3 level engineering studies. The first mainstream engineering learners graduated in November 2015. This is an example of how the company’s investment in educating people impacts the future of young minds in Wentworth and extended communities. Environmental impact Great care is taken to ensure zero harm to the little marine life that exists in the port through efforts in using biodegradable grease on sheet pile clutches, and biodegradable shutter oil and foam seals

for the shutters. No major incidents have occurred to date. The project has been and continues to consistently achieve a score between 96 and 99% for the client as well as external ECO audits. Also, SSA JV have recently been recertified ISO14001 based on the Maydon Wharf project. The CSIR does bi-weekly monitoring during dredging Working over water and in the tidal zone, with piling various piling activities, diving operations and heavy plant and machinery all operating simultaneously in confined work areas, the health and safety of the team was an important aspect of the works. Good working practice and constant educational topics on safety were part of the daily preparations on site. The SSA JV team recently celebrated 1 500 000 LTI free hours in July 2016, a commendable milestone for a project of this complexity and nature.  operations on the berths. Health and safety

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CONSTRUCTION WORLD FEBRUARY 2017