Derivation of Wave Overtopping Formulas for Vertical and Inclined Seawalls Using GMDH Algorithm

Abstract

Since wave overtopping is a complex phenomenon and it is sensitive to hydraulic and structural parameters, hydraulic model tests have been used to estimate the wave overtopping rates at coastal structures. Efforts have also been made toward deriving empirical formulas based on a large amount of accumulated data, e.g. the EurOtop formulas based on the CLASH database. To complement the EurOtop formulas, artificial neural network (ANN) models were presented, which is one of the data models. Other data models have also been developed. On the other hand, Goda developed unified formulas for vertical and inclined seawalls with smooth, impermeable surfaces. In this study, new data-based formulas are developed by using the group method of data handling (GMDH) algorithm with the CLASH and new EurOtop datasets. The GMDH formulas are shown to be more accurate than the Godas formulas and comparable in accuracy to other formulas developed separately for vertical and inclined seawalls. The estimation errors of 95% confidence interval and the range of 95% prediction error are also given. Sensitivity analysis of the derived formulas is also carried out.