Regular wave force on human legs standing on a stepped seawall

Stepped seawalls are a common structure for coastal protection, and pedestrians are prone to approaching them for their recreational benefits. In this study, a series of laboratory experiments and a 3D computational fluid dynamics (CFD) numerical model were conducted to investigate the wave force characteristics of human legs standing on a stepped seawall under regular waves. The dimensionless maximum horizontal wave force on two legs was examined with the related parameters, including incident wave steepness and relative standing height. With the increase in incident wave steepness, the dimensionless maximum horizontal wave force generally increased. With the increase in relative standing height, the tops of the two legs tended to emerge from the submerged condition, and the dimensionless maximum horizontal wave force on the two legs first increased and then decreased. In addition, the aforementioned dimensionless parameters are used to derive a formula for predicting the maximum horizontal wave force on the two legs with relatively high accuracy.