Uncertainties in Redesigning an Existing Quay Wall

A feasibility study was carried out on the redesigning of an existing quay wall of a core harbor in the Netherlands, which was more than 45 years old. The geotechnical behavior of the existing quay wall, especially because of its age, as a response to the maximum load change is undoubtedly the uncertain parameter here. The design and redesign aspects have been considered: the evaluation of the current situation, the remaining lifetime of the structure and other aspects like corrosion and fatigue of the construction materials and the change in design standards between the past and the future situations. No monitoring and measurements were available. Inspection on steel structural elements showed some corrosion, to which extend was unknown. The history of load usage of the quay wall was not registered. After a preliminary redesign, it is clear that some uncertainties would remain. It was concluded that the lack of information in the current situation constitutes the main obstacle to a straightforward redesign and the use of Finite Element Method modelling reveals a failure mechanism, which was not encountered earlier. Because of the technical risks, a redesign of such existing and complex quay wall would necessitate an extensive design procedure to increase reliability