Long Term Modeling of Shoreline Response to Coastal Structures

A Wave Input-Reduction Method Incorporating Initiation of Sediment Motion

“…where ρ s [kg/m 3 ] is the sediment density. The criterion of incipient sediment motion orders that sediment movement occurs only if the Shields parameter θ calculated through Equation (10) is greater than the critical Shields parameter θ cr calculated through Equation (1). This forms the basis of the input-reduction method discussed in the present paper, as waves with rather small wave orbital velocities unable to initiate sand grain motion near the bed are disposed of, since it is considered that these waves have a very small contribution in the medium or long-term shaping of the morphological bed evolution.…”

“…For the long-term estimation of the bed evolution the process-based numerical model MIKE 21 Coupled Model FM [19] was used for the detailed description of hydrodynamics, waves, and sediment transport rates. The model has been used extensively in a variety of coastal engineering applications, with and without the presence of coastal protection structures (e.g., [1,13,37,38]. The MIKE21 Coupled model FM suite includes several complementary numerical models and tools three of which were used for the purpose of this research:…”

“…The prediction of morphological bed evolution and ultimately the shift of the shoreline position due to the complex sediment transport processes that take place in the nearshore area has been of interest for coastal engineers and scientists for many decades. Considering bed and shoreline evolution, two distinct model types can be considered [1], namely the 2DH area models concentrating on the morphological evolution of a given area and the shoreline evolution models, where the changes in shoreline position are modelled through the calculation of the longshore sediment transport rates. The first category of models is used to determine the morphological changes of rather detailed coastal features (such as dunes, or rip channels) based on the simulation of the waves, hydrodynamics and sediment transport rates over a large area (in the scale of many km).…”

Wave, Tide and Topographical Controls on Headland Sand Bypassing

“…(2020) includes a parameterisation of headland bypassing, however this approach is for a simple groyne without consideration of more complex factors present in realistic headlands such as variable sediment coverage. For an approach that robustly deals with bypassing, it is necessary to include computationally intensive process based components to estimate sediment transport (e.g., MIKE ST-SM by DHI; Drønen et al, 2011;Kristensen et al, 2012). Therefore, development of bypassing parameterisations is of direct benefit to these efforts, and the parametric approach described in this paper could be incorporated into any of the above mentioned hybrid approaches.…”

Evaluation of Nourishment Schemes Based on Long-Term Morphological Modeling

“…The concept tries to bridge the gap between existing detailed two-dimensional morphological models and simple one-line models for the coastline evolution and hence is referred to as 1-D hybrid modeling. A first promising application of the hybrid model concept as an engineering tool for predicting effects of offshore breakwaters was given in Drønen et al (2011) and Kristensen et al (2012Kristensen et al ( , 2013a. The hybrid morphological model has now also been used to simulate morphological response to groyne fields (Kristensen et al 2013b).…”