Hydrophysics

Hydrophysics

Estimation of Wave Force Acting on Stepped Porous Seawall

Document Type : Original Article

Authors
Mehdi Esmaeili 1
ُSaeed Farhadypoor 2
1 Department of oceanography, Faculty of Marine Sciences, Chabahar Maritime University, Chabahar, Iran
2 Oceanography and Meteorology Center of Chabahar
Abstract
In this study, the wave-induced force acting on stepped-face porous seawalls was investigated experimentally using physical modeling. Regular waves in a wide range of heights and intervals were investigated. Tests were carried out for a constant water depth of 0.375m and for different inclinations of porous seawall (i.e. θ = 90, 75, 60 and 45 ̊). It was inferred that the factors of relative water depth, wave steepness, the slope of seawall and the surf similarity parameter were effective in predicting the maximum wave force (Fm). The values of Fm for stepped-face seawalls ranged from 3.8–12.8N, and for the vertical porous seawall it was 4.1–16.7N. Comparison the measured values of Fm for different seawalls revealed that the wave-induced forces acting on the stepped-face walls were heavier than the vertical porous wall about 18%. Therefore, the stepped-face seawalls have a better performance compared with the vertical wall in absorbing and dissipating wave energy. Based on the measured data, dimensional analysis and nonlinear regression analysis, new empirical relations are proposed to predict the maximum wave force. These findings were calibrated using SPSS based on the experimental results. The findings of the present investigation can be applied to optimize the design criteria of sloped seawalls for shore protection from erosion.
 
Keywords
Wave force
Stepped seawall
Laboratory modelling
Regular waves
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  • Receive Date 25 May 2022
  • Revise Date 30 July 2022
  • Accept Date 01 August 2022