Hydrophysics

Hydrophysics

Experimental investigation of wave reflection from sloped seawalls

Document Type : Original Article

Author
Mehdi Esmaeili
Department of oceanography, Faculty of Marine Sciences, Chabahar Maritime University, Chabahar, Iran
Abstract
This study is an experimental investigation on the reflective behavior of sloped porous seawalls using physical modeling. Regular waves in a wide range of heights and periods were investigated. Tests were carried out for a constant water depth of 0.27m and for different inclinations of the seawall (i.e. θ = 45, 60, 75 and 90 ̊). It was found that the parameters of wave steepness, relative water depth, surf similarity parameter and the slope of the seawall were influential in predicting the reflection from the sloped porous seawall. The reflection coefficient (Kr) for sloped seawalls ranged from 0.36–0.77 and for the vertical porous seawall it was 0.59–0.83, whereas for the vertical plane wall, it was almost 1. The difference in the wave reflection for the sloped seawalls as compared to the vertical porous seawall was about 28%. New empirical equations were developed for estimating the wave reflection coefficients from the proposed seawalls using nonlinear regression analysis. These equations were calibrated using SPSS based on the experimental results. The results of this study may be useful in the design of energy dissipating vertical quay walls in ports, sloped seawalls for shore protection from erosion and sloped caisson breakwaters.
Keywords
Wave reflection
Sloped seawall
Experimental modeling
Regular waves
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  • Receive Date 13 February 2022
  • Revise Date 29 April 2022
  • Accept Date 18 May 2022