Empirical estimation of beach-face slope and its use for warning of berm erosion

Typical berm erosion and accretion are closely related to the beach-face slope. Empirical equation for prediction of the beach-face slope is proposed. The beach-face slope is expressed as a function of the wave period and the bed sediment grain size. Coefficients in the equation are obtained from three sets of carefully chosen laboratory data through a multiple linear regression with two independent variables using SPSS version 22. The computed correlation coefficient is as high as 0.983, which is believed to justify the validity of the present formulation. A shore profile is split into beach-face and underwater bed profile in the surf zone, and described with two straight lines. Possibility of using the beach-face slope strategically for warning of future berm erosion at the site is proposed.