Showing papers in "Coastal Engineering in 1996"

TL;DR: In this article, the authors investigated the relationship between the erosional properties of combined mud and sand sediments, and found that adding sand to mud, or vice versa, increases the erosion resistance and reduces the erosion rates when the critical shear stress for erosion is exceeded.

TL;DR: In this paper, the results of a fetch limited wind wave growth experiment in water of finite depth are presented, which involved measurements of wind wave spectra, wind speed and direction at eight stations along the fetch.

TL;DR: In this article, the structure of turbulence in a spilling breaker has been studied experimentally based on the transport equation for turbulent kinetic energy (the k-equation), and it is found that diffusive transport plays the most important role in the distribution of turbulence, while advection is important mainly near the surface.

TL;DR: In this paper, the wave set-up on the reef-top and the wave-generated flow across the reef were measured and related to wave and tide level conditions, and it was shown that wave setup is greatest at low tide levels whereas wave generated flow is greater at higher tide levels.

TL;DR: In this article, the transformation and interaction of regular wave trains with submerged permeable structures is modeled using an eigenfunction expansion 3D model and a 2D model based on a mild-slope equation for porous media to account for breakwater slope.

TL;DR: In this paper, the effects of wave groups on the magnitude of the steady state mean wave set-up on two-dimensional reef profiles of various shapes have been compared with data from an idealised horizontal reef with a steep reef-face.

TL;DR: The bottom sediment resuspension is an important process in Cleveland Bay, North Australia as mentioned in this paper, and an iterative method of calculating the bottom shear stress under wave-current motion has been applied.

TL;DR: In this paper, the evolution of the wave spectrum in finite depth, fetch limited conditions are presented. The data were obtained from a series of eight wave gauges established in shallow Lake George, Australia.

TL;DR: In this paper, the influence of sand on the settling and the consolidation of mud has been studied in an extensive set of laboratory experiments and guidelines for modelling the settling of mud/sand mixtures have been formulated.

TL;DR: In this paper, a comprehensive analysis of a comprehensive data set of fetch limited finite depth directional wave spectra is presented, which shows that the spectra are narrowest at the frequency of the spectral peak and gradually broaden for frequencies both greater than and less than that of the peak.

TL;DR: In this article, a wave energy transformation model, which includes wave breaking within the surf zone described by surface rollers, is developed for randomly varying waves over arbitrary bathymetry.

TL;DR: The effect of wave irregularity on submerged permeable structures is analyzed in this article, where the influence of structure geometry, porous material properties and wave characteristics, including oblique incidence, on the kinematics and dynamics over and inside the breakwater is considered.

TL;DR: In this article, a probabilistic model (Wavis-model) was developed to describe the propagation and transformation of individual waves (wave by wave approach) The individual waves shoal until an empirical criterion for breaking is satisfied Wave height decay after breaking is modelled by using an energy dissipation method Wave-induced setup and setdown and breaking-associated longshore currents are also modelled Laboratory and field data were used to calibrate and verify the model.

TL;DR: In this article, the authors investigated the differences in the harbour response when resonance is induced by incident regular free long waves or by incident bound long waves, and the experimental setup allowed the characteristics of the forcing waves to be defined with a good degree of accuracy.

TL;DR: Linear models of time series are used to describe the sequence of the significant wave heights in two locations of the Portuguese coast and it was found that models with orders up to 20, but without all terms, described well the data.

TL;DR: In this paper, a new non-dimensional reflection number R = d t L 0 2 tan β H i D 2 is proposed, which revises the relative weightings of these parameters, and introduces other physically significant parameters, including the local water depth at the toe (dt), and the characteristic armour diameter (D).

TL;DR: In this paper, the wave components within a random (or irregular) sea state are focused to produce a large transient wave group in shallow and intermediate water depths, and the results show that the near-bed velocities are in good agreement with the second-order solution which includes the long wave (or frequency difference terms) first identified by Longuet-Higgins and Stewart.

TL;DR: In this article, a model is proposed that describes short-term changes in beach profile due to attack by storm waves, based on the assumption that the total sediment transport rate q in the nearshore area may be decomposed into two distinct components: rate qW induced by wave/current mechanisms and rate qR generated by run-up flow.

TL;DR: In this paper, the instantaneous sediment concentration in turbulent oscillatory flow over a sand bed was measured at different levels in a large oscillating water tunnel, and the analysis was partly based on Wilson's finding that in sheet flow the equivalent bed roughness is nearly proportional with the Shields parameter, resulting in a roughness/grain diameter ratio much larger than 2.5.

TL;DR: In this paper, an experimental study has been carried out on the forces from plunging breaking regular and irregular waves on a vertical cylinder on a shoal, where total and local wave forces have been measured.

TL;DR: In this article, a new policy was adopted that allowed the coast locally to retreat, producing considerably cost savings, allowing the level of flood protection offered to the Power Station to be increased and reducing the impacts of shingle extraction.

TL;DR: In this paper, a relatively complete physics-based cross-shore sediment transport model, including mechanisms for suspended and bedload transport, is developed with the capacity for onshore and offshore transport.

TL;DR: In this paper, a movable sled was instrumented with pressure, current, and wind sensors to measure wave and wind forcing during the Superduck experiment, and mean currents and bottom shear stress at various locations across the surf zone were determined.

TL;DR: In this paper, a coupled bay-river system is analyzed, and it is shown that if a semi-infinite river is in presence, that is, if there is at least a part of the boundary of the bay through which the resonant wave energy may be radiated, the harbor paradox seems to be no longer an appropriate statement.

TL;DR: In this article, the joint distribution of consecutive wave heights in a real sea state was evaluated by a simulation methodology that is consistent with the Gaussian random wave model, and the resulting predictions of run and group length statistics differ from the Kimura theory.

TL;DR: In this paper, the authors derived general stability models based on the acting wave forces, method of placement, type and direction of movement, and other physical quantities affecting the stability of a spherical armor unit in a submerged widecrown breakwater.

TL;DR: In this article, a numerical model is proposed for the simulation of long-period water surface fluctuations forced by short-period wave groups, based on the generalized conservation equations of mass and momentum.

TL;DR: In this article, the authors studied the natural and wave-induced oscillations in Nagasaki Bay, a coupled bay-river system, and numerically proved that the bay at the mean tidal level has natural modes of periods of 30.60 minutes, 17.28 minutes, 10.08 minutes, 7.67 minutes, etc.

TL;DR: In this article, a mathematical model was developed to predict the wave-induced motion of the fluid mud in a submarine rectangular trench to time-periodic surface waves propagating over the trench has been studied experimentally and theoretically.