Towards a Practical Application of Numerical Models to Predict Wave-Structure Interaction: An Initial Validation

A more detailed understanding of porous flow inside a rubble-mound structure may have potential benefits in breakwater design. Numerical models are expected to be a useful additional research tool in this field, provided that their calculation results can be validated against measurements. This paper presents the results of a systematic effort...

Optimal inspection planning with time-dependent reliability analysis, application to rubble-mound breakwaters

In order to avoid failure in its lifetime, a breakwater system has to be inspected and, if necessary, has to be repaired. In this paper, a comprehensive maintenance strategy with optimal inspection planning is formulated. Rational maintenance decision-making approaches are discussed. The proposed maintenance strategy combines time-dependent and...

Optimal inspection strategy for rubble-mound breakwaters with time-dependent reliability analysis

This paper presents a comprehensive maintenance strategy with optimal inspection planning and its application to rubble mound breakwaters. In order to fulfil designated functions, a breakwater has to be inspected during its lifetime and has to be repaired if necessary. Actions of inspecting and repairing form a maintenance strategy. In the paper...

Optimisation of Structural Systems by Appropriately Assigning Probabilities of Failure: Application to Rubble Mound Breakwaters

An appropriate assignment of probabilities of failure to subsystems and components in a structural system can bring a minimum of costs and risk. In this paper, a method for economic optimisation of rubble mound breakwaters using pre-assigned probabilities of failure is presented. Application to a design case shows that the proposed method is...

Breakwaters and closure dams (2nd edition)

Classical, Innovative and Unconventional Coastline Protection Methods

This paper gives an overview of some recent developments in structures for coastal protection. Single layer units like Accropode and Xbloc are rather popular at this moment; research indicates that also cubes can be placed in single layers. Also the use of heavy aggregates in concrete can be beneficial for the stability and economics. Structures...

Riprap stability on the inner slopes of medium-height breakwaters

Medium height breakwaters are subjected to a considerable amount of overtopping. This implies the armour on the inner slope has to stable against overtopping waves. Existing equations do lack some basic understanding of the process of starting up movement of rock on the inner slopes. In order to get more insight into this phenomenon a special...

Influence of the density of placement on the stability of armour layers on breakwaters

Studies on the stability of the amour layer (d’Angremond et. al. [1999] revealed the importance of density of placement. The current research focuses on the influence of the density of placement on the stability of cubes in a double armour layer and tetrapods and rocks in a single armour layer. The experiments were performed in the Laboratory of...

Positioning of cubes on a breakwater slope

Recent research has shown that it is possible to use concrete cubes as a single armour layer on breakwaters. However, this is only possible in case a placing density of at least 70 % is achieved. In lab-tests it is no problem to place cubes with this density, however it is questionable if such a placing density can be achieved in prototype...

Criteria for the selection of breakwater types

In history PIANC has paid quite some attentions to breakwaters, in ancient years results of practical experience have been published in the country presentations at the Conferences, but later some of these papers started to have a more scientific basis. One of the first papers giving a good background on the processes of stability of breakwaters...

Probability and port engineering

One of the major problems in the design of coastal structures is that the design has to be based on very uncertain input data. This implies that the degree of uncertainty is an important value for the designer. In traditional design the uncertainty is not really quantified, but an overall “safety factor” is included. The problem of this approach...