Three-Dimensional Model for Predicting Beach Changes Based on Bagnold’s Concept

Serizawa²,

Miyahara³

2012

Self Cite

In a slender water body with a large aspect ratio, the angle between the direction normal to the shoreline and the wave direction exceeds 45°, resulting in the emergence of cuspate forelands and the subdivision of a lake, because wind fetch along the principal axis becomes long. In this study, the BG model (a three-dimensional model for predicting beach changes based on Bagnold's concept) was applied to this problem. The 3-D subdivision process of a long slender water body was predicted.

“…(1), which is expressed using the wave energy at the breaking point, was used, similar to the BG model (Serizawa et al, 2006). The variables in Eq.…”

Section: Predictive Modelmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Numerical Simulation of Three-Dimensional Segmentation of Elongated Water Body Using Bg Model

Serizawa²,

Miyahara³

2012

Self Cite

“…For the equation of sediment transport due to waves, the equation given by Serizawa et al (2006) was employed, which was derived by applying the concept of the equilibrium slope introduced by Inman and Bagnold (1963) and the energetic approach by Bagnold (1963), similar to the previous study (Serizawa et al, 2008). Consider Cartesian coordinates (x, y), where the x-axis and y-axis are taken to be the cross-shore distance (positive for shoreward) and longshore distance parallel to the shoreline, respectively.…”

Section: Modelmentioning

confidence: 99%

“…Regarding Eqs. (2) and (3), Serizawa et al (2008) used the sediment transport equation proposed by Serizawa et al (2006) by setting the index of wave direction reversal λ to be 0. This implicitly assumes that the coefficients of cross-shore and longshore sand transport are equivalent.…”

Section: Modelmentioning

confidence: 99%

Prediction of Formation of Dynamically Stable Ebb Tidal Delta and Measures for Preventing Offshore Sand Loss

Serizawa²,

San-Nami³

et al. 2011

Self Cite

We developed a model for predicting the evolution of an ebb tidal delta based on the BG model, which was proposed by the present authors using the Bagnold concept of the equilibrium slope. Bathymetric changes around the inlet of Imagire-guchi between 1978 and 2005 were quantitatively analyzed to investigate the evolution of the ebb tidal delta and sand deposition offshore of the inlet. The model was applied to this inlet. The predicted bathymetric changes were in good agreement with the measured changes. Some measures for preventing the offshore sand loss were also considered by applying the model. The most effective measure was predicted to be cross-shore sand bypassing.

“…The discharge of part of the nourished sand is attributed to this large wave incidence angle. In this study, the effect of this oblique wave incidence with a large angle on the beach changes was investigated through the analysis of monitoring survey data and a numerical study using the BG model, which was proposed by Serizawa et al (2006), and the effectiveness of a spur dike as a measure to stabilize the beach was studied. …”

Section: Introductionmentioning

confidence: 99%

Formation of Dynamically Stable Lakeshore Under Seasonally Changing Wave Direction

Ishikawa

San-Nami³

et al. 2011

Self Cite

In the Ukishima region of Lake Kasumigaura, beach nourishment along with the construction of groins has been carried out to recover a sandy beach. After the beach nourishment, part of the nourishment sand was transported away from the beach, turning around the tip of the downcoast groin owing to the oblique wave incidence in winter. To enhance the stability of the beach, the groins were extended and a spur dike was constructed. To design these structures, a numerical simulation using the BG model was carried out, and the optimum shapes were determined by taking into account the seasonally changing wave direction. The effectiveness of the spur dike was numerically evaluated using the BG model.