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Stive, M.J.F. (author), Terrile, E. (author), Reniers, A.J.H.M. (author), Verhagen, H.J. (author)
Threshold of motion of coarse particles under regular shoaling waves is studied. Experiments were performed to investigate the effects of bed fluid acceleration on coarse particle stability. By varying wave height, wave period and water depth combinations of similar peak orbital velocities and weak to strong intra-wave accelerations were created...
conference paper 2005
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De Schipper, M.A. (author), Ranasinghe, R.W.M.R.J.B. (author), Reniers, A.J.H.M. (author), Stive, M.J.F. (author)
Nearshore rhythmicity is often initiated in the period just after a storm where the subtidal bar is turned alongshore uniform. The initiation time as well as the length scales of the created rhythmicity varies from one storm period to another. Here we show that the post-storm wave conditions are related to the initiation of the morphological...
conference paper 2010
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Bosboom, J. (author), Reniers, A.J.H.M. (author)
Although it is generally acknowledged that the practical predictability at smaller scales may be limited, output of high-resolution morphodynamic area models is mostly presented at the resolution of the computational grid. The so- presented fields typically are realistic looking, but not necessarily of similar quality at all spatial scales....
conference paper 2014
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De Schipper, M.A. (author), De Vries, S. (author), Ranasinghe, R.W.M.R.J.B. (author), Reniers, A.J.H.M. (author), Stive, M.J.F. (author)
Typically a beach is out of equilibrium after a nourishment is installed. To observe how a nourished beach behaves on the timescale of storms a monitoring campaign was set up at Vlugtenburg beach after a nourishment in the spring of 2009. Here we show a sediment budget analysis of the first 2.5 years for a coastal domain spanning 1750 m...
conference paper 2012
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Van Rooijen, A. (author), Reniers, A. (author), Van Thiel de Vries, J.S.M. (author), Blenkinsopp, C. (author), McCall, R. (author)
A one-dimensional hydrostatic version of the XBeach model (Roelvink et al., 2009) is applied to hindcast swash morphodynamics measured during an accretive, and an erosive tide at Le Truc Vert beach (France) in early spring 2008 (Masselink et. al, 2009; Blenkinsopp et al., 2011). Swash hydrodynamics are solved by applying the nonlinear shallow...
conference paper 2012
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Stive, M.J.F. (author), Reniers, A.J.H.M. (author), Terrile, E. (author), Verhagen, H.J. (author)
The threshold of motion of coarse particles under regular shoaling waves is studied. Experiments are performed to investigate the effects of bed fluid acceleration on coarse particle stability. By varying wave height, wave period and water depth, combinations of similar peak orbital velocities and weak to strong intra-wave accelerations were...
conference paper 2005
document
Smit, M. (author), Reniers, A. (author), Stive, M.J.F. (author)
Nearshore sandbars appear with various patterns which may change over time. From observations, these changes seem to be related to changes in hydrodynamic conditions, although observed length scales could not be related directly to occurring wave conditions. The current work investigated the role of both the concurrent and previous hydrodynamics...
conference paper 2010
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Henriquez, M. (author), Reniers, A. (author), Ruessink, G. (author), Stive, M.J.F. (author)
To study onshore bar migration and the accompanying intra-wave sediment transport a wave flume experiment was conducted. The wave flume had a rigid bottom with a single bar profile. The focus of the experiment was to measure the hydrodynamics in the wave bottom boundary layer. The results show that the skewness of bottom stress is not only...
conference paper 2010
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Radermacher, M. (author), Zeelenberg, W. (author), De Schipper, M. (author), Reniers, A. (author)
Large beach nourishments are often considered an efficient way to deal with coastal zone management issues, notably coastal erosion. Such large nourishments can act as a geometric perturbation, which might cause the tidal current to detach from the coastline. The Sand Motor is a mega-scale beach nourishment in the Netherlands. Field observations...
conference paper 2015
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Van Thiel de Vries, J.S.M. (author), Van Dongeren, A.R. (author), McCall, R. (author), Reniers, A. (author)
The effect of the longshore dimension on dune erosion is examined numerically with a 2DH process based model XBeach. Exploratory simulations are presented to examine longshore effects due to directionally spread waves, longshore variation in topography and longshore variation in bathymetry. The simulations reveal that alongshore sediment...
conference paper 2011
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De Schipper, M.A. (author), De Vries, S. (author), Henriquez, M. (author), Reniers, A.J.H.M. (author), De Koning Gans, H.J. (author), Labeur, R.J. (author), Stive, M.J.F. (author)
In this paper a new wave pool concept is presented using ship hulls as wave generators. To evaluate the potential of such a concept a towing tank experiment is conducted to investigate ship wave generation in a confined space. In the towing tank experiment various hull sizes and velocities are examined to maximize the generated wave height. The...
conference paper 2009
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Henriquez, M. (author), Reniers, A.J.H.M. (author), Ruessink, B.G. (author), Stive, M.J.F. (author), Stanton, T.P. (author), Foster, D.L. (author)
Scale relations are necessary to choose proper sediment for physical models. The use of lightweight artificial sediment makes it possible to preserve the Reynolds number, Shields number and relative settling velocity altogether. There is also the possibility to preserve the Shields number in combination with the Dean number which would be more...
conference paper 2009
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Henriquez, M. (author), Reniers, A.J.H.M. (author), Ruessink, B.G. (author), Stive, M.J.F. (author)
The cause of sediment suspension events during flow reversal under waves in the nearshore is not well understood. Vortex tubes and horizontal pressure gradients have been suggested to be the cause of the suspension events. A medium sized wave flume experiment has been conducted to give insight in the hydrodynamics of the wave bottom boundary...
conference paper 2012
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Bosboom, J. (author), Reniers, A.J.H.M. (author)
The quality of a morphological prediction is often expressed by an overall grid-point based skill score based on the Mean Squared Error (MSE) between the predicted and observed bed levels (Sutherland et al., 2004). Although the MSE is a good measure of the overall error between model and observations, it tends to penalize rather than reward the...
conference paper 2013
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De Schipper, M.A. (author), De Vries, S. (author), Ranasinghe, R.W.M.R.J.B. (author), Reniers, A. (author), Stive, M.J.F. (author)
The present paper examines the generation and inter-annual evolution of alongshore variability in topography measured after the implementation of a sand nourishment. The magnitude of the topographic variability is quantified using 3.5 years of monthly survey data. The emergence and temporal change in alongshore morphological variability is...
conference paper 2013
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De Schipper, M.A. (author), Reniers, A. (author), MacMahan, J. (author), Ranasinghe, R.W.M.R.J.B. (author)
Field observations and numerical model simulations are examined to investigate the magnitude of vortical very low frequency (VLF) velocity fluctuations (i.e. large scale surfzone eddies) under different offshore wave forcing. Observations of vortical VLF motions under shore -normal wave incidence at Duck, NC, USA are re-analyzed and compared...
conference paper 2012
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Radermacher, M. (author), Thackeray, Z.H. (author), De Schipper, M.A. (author), Gordon, L. (author), Chrystal, C. (author), Leuci, R. (author), Reniers, A.J.H.M. (author)
Measurements of nearshore currents can be performed using a range of existing measurement techniques. Although every technique has its specific benefits, capturing strong spatial gradients in a flow field with sufficiently high spatial resolution often proves to be difficult due to high costs or practical difficulties associated with these...
conference paper 2015
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Van Rooijen, A.A. (author), Van Thiel de Vries, J.S.M. (author), McCall, R.T. (author), Van Dongeren, A.R. (author), Roelvink, J.A. (author), Reniers, A.J.H.M. (author)
Over the past decades the effect of vegetation (e.g. kelp, mangroves, sea grass) on nearshore coastal processes has received more and more attention. In recent years several numerical wave models have been extended to include this effect. In the current study, the numerical storm impact model XBeach was extended with formulations found in...
conference paper 2015
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van Nunen, K.L.L. (author), Swuste, P.H.J.J. (author), Reniers, G.L.L.M.E. (author)
Een Belgisch bedrijf uit de maakindustrie gebruikt palletwagens voor intern transport. Ondanks de veiligheidsinspanningen komen ongevallen met palletwagens frequent voor. Om arbeidsongevallen te beheersen is het belangrijk om een goed zicht te hebben op de potentiële ongevalsscenario’s in het bedrijf. De BowTie- of het vlinderdasmodel is een...
conference paper 2019
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Brocal, Francisco (author), González-Gaya, G. (author), Sebastián, Miguel A. (author), Reniers, G.L.L.M.E. (author), Paltrinieri, Nicola (author)
As a result of the important and rapid technological advances in industrial processes, in recent years the scientific interest in the field of occupational health and safety (OH&S) is increasing. This scenario of continuous change generates both new opportunities and new challenges in the workplace. This circumstance allows eliminating or...
conference paper 2019
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