Set-Up due to Random Waves: Influence of the Directional Spectrum

Abstract

This paper deals with the estimation of set-up due to irregular waves. Following the logic of Barbaro and Martino [1], it is derived the analytical expression of the set-up. The solution is based on the hypotheses of straight, parallel depth contours and constant average flow parameters in the longshore direction. In this context, the corresponding value of the set-up is calculated from a specified off-shore directional spectrum. The effect of the assumed directional spectrum is investigated. In particular, set-up is estimated by considering the following frequency spectra: Pierson-Moskowitz [2], JONSWAP [3] and Ochi-Hubble [4]. Further, influence of the spreading function is investigated by assuming a cosine-power [5] and a hyperbolic spreading function [6]. It is shown that the assumed off-shore spectrum significantly modifies the estimated set-up. It is proposed a practical application. The estimation has been carried out by considering various Italian and American locations. The model is applied from buoy data, that are provided by ISPRA (Istituto Superiore per la Protezione e la Ricerca Ambientale) and by NDBC (National Data Buoy Center).

Analysis, evaluation and innovative methodologies to prevent coastal erosion

“…The new expression of set-up due to irregular waves (Barbaro et al [1]) was obtained following the logic of Longuet-Higgins [19] for regular waves, and following the logic of Barbaro and Martino [20]. The model is based on the assumption that the contour lines are straight and parallel to the x-axis and that the seabed is flat.…”

“…The prediction and management of shoreline evolution are necessary to protect coasts. Shoreline evolution is caused by many physical factors, such as intensity and duration of a sea storm (Arena et al [5]), design wave (Barbaro [6]), maximum wave forces on structures (Barbaro [7]; Boccotti et al [8,9]; Romolo et al [10]), longshore sediment transport (Tomasicchio et al [3]), set-up (Barbaro et al [1]), run-up (Barbaro et al [2]). Shoreline evolution that can be described on three different temporal scales: geological (lasting for hundreds of years), long-term (lasting from a few years to tens of years), and short-term (lasting for a few months).…”

Historical Evolution of the Shoreline of Reggio Calabria

“…Many studies confirms that it is important to protect them and that set-up [25,26], run-up [27], the duration and the intensity of the sea storm are the principal causes of their erosion [28][29][30].…”

Risk Mapping of Coastal Flooding Areas. Case Studies: Scilla and Monasterace (Italy)

“…Regarding the anthropic factors, the most important are the construction of infrastructures, ports and coastal defense works [13][14][15]. Amongst the natural factors, wave action and longshore and river transport are of particular importance [16][17][18][19][20][21][22][23][24][25].…”