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Dorst, K. (author), Provoost, Y. (author), Verhagen, H.J. (author)
A revetment of pattern placed elements, or a so called pitching, is used worldwide to protect shorelines and embankments. Also in The Netherlands more than 500 km of river, lake and sea dikes is protected by pitchings. Until the 60’s the design and construction of pitchings was based on experience. After the first damages on pitchings and the...
conference paper 2012
document
Verhagen, H.J. (author)
Apart from many ecological advantages, mangroves in front of a coastal defence may lower the construction and maintenance costs of the defence. Although mangroves have hardly any reducing effect on water levels (and on tsunami impact) mangroves may significantly reduce wave attack on a coastal dike, and in this way reduce the cost of a revetment...
conference paper 2012
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Tuan, T.Q. (author), Verhagen, H.J. (author)
Extensive laboratory experiments were carried out to investigate wave overtopping on seadikes with (vertical) crown-walls in Vietnam. It is shown that the wave overtopping reduction by walls is inadequately, although rather complexly, described by TAW-2002. A new approach has been developed, which can straightforwardly be incorporated in the...
conference paper 2012
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Trung, L.H. (author), Verhagen, H.J. (author), Van der Meer, J.W. (author), Cat, V.M. (author)
The landware slopes of sea dikes in the north of Vietnam are steep and solely constructed by soil covered with grass due to the budget constraints and also the out-of-date design guidelines.The resistance against erosion due to wave overtopping of several grass covered slopes were tested with the Wave Overtopping Simulator to show if a slope...
conference paper 2012
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Veerman, H. (author), Van Kleef, A. (author), Wokke, F. (author), Ober, O. (author), Tiberius, C.C.J.M. (author), Verhagen, A.A. (author), Bos, A. (author), Mieremet, A. (author)
The paper presents a short introduction to the mathematical theory of the EVT, the consecutive steps that are made in the software tool to address MI probability estimation and proof of range error distribution overbounding. Finally some early results obtained by GIMAT are presented.
conference paper 2012
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Marchand, M. (author), Thu, H.T.Y. (author), Verhagen, H.J. (author)
book chapter 2011
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Tsimopoulou, V. (author), Kanning, W. (author), Voortman, H.G. (author), Verhagen, H.J. (author)
One of the failure mechanisms of a rubble mound breakwater is the failure of its armour layer. In order to determine the stability of an armour layer, the design load has to be defined, which is in fact the wave that attacks the structure. Being a highly stochastic phenomenon, the wave action is not easily defined, while there is always some...
conference paper 2011
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Burgmeijer, M.A. (author), Verhagen, H.J. (author), Van der Wegen, M. (author)
Integrated Coastal Zone Management (ICZM) is an interdisciplinary process by definition. Individual actors in CZM need to cooperate and communicate to come to an optimum management strategy for the coastal zone. Because engineers focus on finding the “best” solution in engineering terms, they often are quite surprised that in the end of the day...
conference paper 2011
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Verhagen, A.A. (author), Teunissen, P.J.G. (author), Van der Marel, H. (author), Li, B. (author)
A key issue with GNSS carrier phase ambiguity resolution is that often the full set of ambiguities cannot be fixed fast and reliably. A possible strategy is then to resolve only a subset of ambiguities, one for which the probability of correct fixing, the so-called success rate, is sufficiently close to 1. However, a proper subset selection...
conference paper 2011
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Trung, L.H. (author), Verhagen, H.J. (author), Van der Meer, J.W. (author)
The Simulator was applied to test the resistance against wave overtopping of grass covered dike slopes in Viet Nam. Observation and measurement during destructive tests were performed to investigate the development process of damage induced by overtopping flow. Damages were likely to be initiated at transition of either geometry or materials, at...
conference paper 2011
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Tsimopoulou, V. (author), Kanning, W. (author), Verhagen, H.J. (author), Vrijling, J.K. (author)
This paper presents the development of a semi-probabilistic method for armour layer design of rubble mound breakwaters, which is based on the use of safety factors. The objective is to introduce an approach that is both attractive to designers and sufficiently reliable when a high degree of uncertainty is involved in the design process. The main...
conference paper 2011
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Verhagen, H.J. (author), Jumelet, D. (author), Vilaplana Domingo, A. (author), Van Broekhoven, P. (author)
In de Van der Meer formulas for armour stability the Notional Permeability is used as a parameter. Unfortunately the physical basis of this parameter is weak. It is therefore suggested to use a relation between the Notional Permeability P and the reduction of wave run-up due to infiltration into the breakwater. The advantage is that the latter...
conference paper 2011
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Trung, L.H. (author), Van der Meer, J.W. (author), Luong, N.Q. (author), Verhagen, H.J. (author), Schiereck, G.J. (author)
The resistance of various grassed slopes against wave overtopping has been appraised by means of the Wave Overtopping Simulator in situ for a couple of years in Viet Nam. Destructive test results show that a dike slope covered with grass could suffer a certain overtopping discharge not smaller than 20 l/s per m. During testing it was difficult...
conference paper 2011
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Hoan, N.T. (author), Stive, M.J.F. (author), Booij, R. (author), Hofland, B. (author), Verhagen, H.J. (author)
This paper presents the results of an experimental study on stone stability under nonuniform turbulent flow, in particular expanding flow. Detailed measurements of both flow and turbulence and the bed stability are described. Than various manners of quantifying the hydraulic loads exerted on the stones on a bed are extensively reviewed and...
journal article 2011
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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 2011
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Van Engelen, A. (author), De Bruijne, M. (author), Klein, S. (author), Verhagen, H. (author), Groen, H. (author), Wentzel, J. (author), Van der Ligt, A. (author), Niessen, W. (author)
Automatic quantification of carotid artery plaque composition is important in the development of methods that distinguish vulnerable from stable plaques. MRI has shown to be capable of imaging different components noninvasively. We present a new plaque classification method which uses 3D registration of histology data with ex vivo MRI data,...
conference paper 2011
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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
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Narayan, S. (author), Suzuki, T. (author), Stive, M.J.F. (author), Verhagen, H.J. (author), Ursem, W.N.J. (author), Ranasinghe, R. (author)
A study of the effectiveness of mangroves in attenuating cyclone- induced waves was done using the SWAN 40.81 numerical model. Hydraulic parameters during extreme events and local mangrove vegetation parameters were estimated for the Kanika Sands mangrove island near the upcoming Dhamra Port in Orissa, India. Simplified generic analyses were...
conference paper 2010
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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
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Bisschop, F. (author), Visser, P.J. (author), Van Rhee, C. (author), Verhagen, H.J. (author)
Convential models for the erosion of non-cohesive sediments overestimate the erosion rate induced by high flow velocities. These high flow velocities occur, for instance, in breaching of embankments or dunes (flow velocities up to 10 m/s) or in jetting sand with a trailing suction hopper dredger (30 to 60 m/s). At these very large flow...
conference paper 2010
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