Laboratory and Analytical Study of Wave-Force Interactions on At Grade and Elevated Vertical Walls

Climate change is increasing the vulnerability of nearshore structures to large wave forces; thus, it is important to accurately predict these forces to protect coastal nearshore infrastructure. Therefore, experiments were conducted to measure wave forces and pressures on a vertical wall, with geometry representative of a seawall or wall of a nearshore building. This experiment investigated the effects of elevating the wall, in small increments, on wave-induced pressures and forces. The validity of recommended design equations for predicting wave forces on coastal infrastructure were evaluated by comparing predicted forces and pressures at the stillwater level with measurements from the physical model. In addition, a relationship between wall elevation and measured wave force was developed by comparing the normalized force for a wave condition to a blockage coefficient. The blockage coefficient is derived from the ratio of the submerged area of the wall to the wetted area of the flume cross section.