- document
-
Vanlishout, V. (author), Verhagen, H.J. (author), Troch, P. (author)There is a growing interest in the application of submerged rubble mound breakwaters as coastal defence structures. As their defensive ability highly depends on the amount of wave energy remaining at their lee side, the accurate prediction of the energy in the lee of such structures is of utmost importance. Past experiments have shown that the...conference paper 2010
- document
-
Baart, S. (author), Ebbens, R. (author), Nammuni-Krohn, J. (author), Verhagen, H.J. (author)Present design tools, as found in the Rock Manual or Coastal Engineering Manual, for the determination of toe rock size for rubble mound breakwaters are based on test data with a large spread: data is relatively dispersed around the centre and descriptive equations have limited applicability ranges. New research has been undertaken to contribute...conference paper 2010
- document
-
Nguyen, D.V. (author), Van Gelder, P.H.A.J.M. (author), Verhagen, H.J. (author), Vrijling, J.K. (author)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...conference paper 2010
- document
-
Verhagen, H.J. (author)In the ROCK MANUAL (2007) some guidance is given for the design of toes for breakwaters. However, for very shallow toes, as well as for very wide toes (or berms) this guidance is only marginally. Recently a number of shallow berms and toes have been constructed, partly with the intention to lower the height of the breakwater. These works showed...conference paper 2010
- document
-
Nguyen, D.V. (author), Van Gelder, P.H.A.J.M. (author), Verhagen, H.J. (author), Vrijling, J.K. (author)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...conference paper 2010
- document
-
Allsop, N.W.H. (author), Cork, R.S. (author), Verhagen, H.J. (author)This paper introduces a co-operative project between HR Wallingford UK (HRW) and Delft University of Technology, Netherlands, (TUD) to develop, populate, and then to apply a database on all major breakwaters around the world. It builds on, and revives, similar initiatives that originate in the late 1970s. The paper describes the objectives in...conference paper 2009
- document
-
Verhagen, H.J. (author), Mertens, M. (author)In the Rock Manual [2007] two sets of equations for the determination of rock stability in breakwaters armour layers are presented. One set is the original formula presented by Van der Meer [1988], valid for deep water conditions. This set uses the parameters Hs and Tm. The other set is an adaptation of these formulae, using the parameters H2%...conference paper 2009
- document
-
De Rover, R. (author), Verhagen, H.J. (author), Van den Berge, A. (author), Reedijk, B. (author)The effect of single layer interlocking armour unit breakage on the hydraulic armour layer stability and potential damage progression is addressed in this paper. A 2-dimensional scale model of a rubble mound breakwater with an armour layer consisting of Xbloc armour units was tested. The residual armour layer stability with broken units was...conference paper 2008
- document
-
Viet, N.D. (author), Verhagen, H.J. (author), Van Gelder, P.H.A.J.M. (author), Vrijling, J.K. (author)In 2006 a Vietnamese Engineering Consultancy Company carried out a design study of a Naval Base at the location of the South of Doson Peninsula in Vietnam. A deterministic approach applied to the conceptual design of the breakwater system of the Naval Base resulted in a cross-section with a big armour layer and a rather low crest level. This...conference paper 2008
- document
-
Viet, N.D. (author), Verhagen, H.J. (author), Van Gelder, P.H.A.J.M. (author), Vrijling, J.K. (author)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...conference paper 2008
- document
- d'Angremond, K. (author), van Roode, F. (author), Verhagen, H.J. (author) lecture notes 2008
- document
-
Verhagen, H.J. (author)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...conference paper 2004
- document
-
Verhagen, H.J. (author)In a classical design approach to breakwaters a design wave height is determined, and filled in into a design formula. Some undefined safety is added. In the method using partial safety coefficients (as developed by PIANC [1992] and recently also adopted by the Coastal Engineering Manual of the US Army Corps of Engineers [CEM [2003]) the degree...conference paper 2003
- document
-
Verhagen, H.J. (author), Van Dijk, B. (author), Nederpel, A. (author)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...conference paper 2003
- document
-
Van den Bosch, A. (author), D' Angremond, K. (author), Verhagen, H.J. (author), Olthof, J. (author)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...conference paper 2002
- document
-
Verhagen, H.J. (author), D' Angremond, K. (author), Van der Vliet, K. (author)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...conference paper 2002
- document
-
Verhagen, H.J. (author)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...conference paper 2002
- document
-
Sundar, V. (author), D' Angremond, K. (author)(1) Functional requirements for Breakwaters - Prof. K.d' Angremond (2) Development of fishery harbors in India - Mr. K. Omprakash (3) Non-rubble Breakwaters and optimisation - Prof. K.d' Angremond (4) Wave energy caisson Breakwaters - Dr. S. Neelamani (5) Partially suspended porous wall Breakwaters - Dr. J.S. Mani (6) Case studies on stability...book 2000
- document
-
Verhagen, H.J. (author)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...conference paper 2000
- document
-
Oumeraci, H. (author), Allsop, N.W.H. (author), De Groot, M.B. (author), Crouch, R.S. (author), Vrijling, J.K. (author)Final report and appendices of the European project Proverbs on tools for the design of vertical breakwaters (caisson type breakwaters) and similar hydraulic structures in the coastal zone. It includes the loads (waves) as well as the strength of the structure (geotechnial aspects, structural aspects)book 1999