How to Cite

LONG-WAVE MITIGATION STUDY FOR THE PORT OF NGQURA. (2020). Coastal Engineering Proceedings, 36v, papers.28. https://doi.org/10.9753/icce.v36v.papers.28


Solutions to the long-wave induced moored ship motion problems at the Port of Ngqura were investigated in this study. Long-wave mitigation options were modelled with various layout modifications to the present model of the port, which has been validated with measured data. The numerical model simulations were used to derive long-term data sets inside the Port. Several moored ship motion simulations, using alternative conventional and dynamic mooring options, were performed for an extreme wave and wind condition for each berth at the port. Preferred port layout options and optimal mooring solutions were then determined for each berth. A complete framework of wave and ship motion simulations were performed for the preferred mitigation options. The ship motions and mooring line forces were determined for the relevant vessels at selected berths. This allowed for berth operability and downtime statistics to be determined, taking the limiting wave height and allowable mooring line criteria into account. Since several port layout options and different mooring arrangements were assessed, a Multi-Criteria-Analysis (MCA) was followed to determine the best possible solution.

Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/y79b158riGE


BSI, 2013. BS 6349-1-1: 2013. Maritime works. General. Code of planning and design for operations. BSI London, UK.

Goda, Y., 2010. Random seas and design of maritime structures. World scientific.

Holthuijsen, L.H., 2010. Waves in oceanic and coastal waters. Cambridge university press.

Moes, H., Terblanche, L., 2010. Motion criteria for the efficient (Un) loading of container vessels.

PIANC, 2012. Criteria for the (un) loading of container vessels. Report No. 115 2012.

PIANC, 1995. Criteria for movements of moored ships in harbours. PIANC Brussels.

Reniers, A., Roelvink, D., Dongeren, A. van, 2001. Morphodynamic response to wave group forcing, in: Coastal Engineering 2000. pp. 3218–3228.

Reniers, A.J., Roelvink, J.A., Thornton, E.B., 2004. Morphodynamic modeling of an embayed beach under wave group forcing. Journal of Geophysical Research: Oceans 109.

Rossouw, M., Terblanche, L., Moes, J., 2013. General characteristics of long waves around the South African coast, in: Coasts and Ports 2013: 21st Australasian Coastal and Ocean Engineering Conference and the 14th Australasian Port and Harbour Conference. Engineers Australia, p. 653.

Terblanche, L., van der Molen, W., 2013. Numerical modelling of long waves and moored ship motions, in: Coasts and Ports 2013: 21st Australasian Coastal and Ocean Engineering Conference and the 14th Australasian Port and Harbour Conference. Engineers Australia, p. 757.

Thompson, P., Cai, Y., Reeve, D., Stander, J., 2009. Automated threshold selection methods for extreme wave analysis. Coastal Engineering 56, 1013–1021.

Van der Molen, W., 2003. Long-period wave forces on a moored ship in a harbour using a strip theory approach, in: Proc. 2nd Int. Conf. on Port and Maritime R&D and Technology (Singapore), 2003. pp. 113–120.

Van Der Molen, W., Monardez, P., Van Dongeren, A.P., 2006. Numerical simulation of long-period waves and ship motions in Tomakomai Port, Japan. Coastal engineering journal 48, 59–79.

van der Molen, W., Rossouw, M., Phelp, D., Tulsi, K., Terblanche, L., 2010. Innovative technologies to accurately model waves and moored ship motions.

van der Molen, W., Scott, D., Taylor, D., Elliott, T., 2016. Improvement of mooring configurations in Geraldton Harbour. Journal of Marine Science and Engineering 4, 3.

Yamano, T., 1997. An estimation method of wind force acting on ship’s hull. Journal of the Kansai society of naval architects, Japan 228.

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