Julien De Rouck, Koen Van Doorslaer, Jan Goemaere, Hadewych Verhaeghe


Two new breakwaters are being constructed to protect the renewed harbour entrance in Ostend, Belgium. In this paper, both the hydraulic design and geotechnical design are discussed. For the hydraulic design, model tests have been carried out in a 2-D wave flume to optimise the cross section. Stability of the final breakwater, with special attention to the crest element and the armour unit HARO, and stability during the construction phases were tested. The geotechnical design, especially of the north-western breakwater, was an engineering challenge since it is located above a thick layer of very soft soil. A combination of building in stages (consolidation time) and providing a strong reinforcement (geotextile) solved this issue.


hydraulic stability, HARO, geotechnical stability, geotextile, soft soil, consolidation time


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