Abstract:
Extreme wave is the key parameter for engineering design on reefs. In this research, a 1: 15 physical model is used to study the influences of revetments on extreme wave propagation characteristics in a large wave flume of Tianjin Research Institute for Water and Transport Engineering. Wave shape, wave setup, wave celerity and wave spectrum are analyzed. The experimental results show that construction of revetment has notable water-blocking effect. From the aspect of wave shape, the influence of reflection wave makes waves break more intensely at the reef edge. Wave setup increases significantly on the reef with revetment than without revetment. The maximum wave setup is 4 times of that of the natural reef. The influences of revetment on wave setup become more significant as wave period decreases. Wave celerity decreases by 20% ~35% after construction of revetment. Regarding the spectrum, the existence of revetment makes the nonlinear interaction of waves more complex. The peak frequency energy of waves at the reef edge is lower, but the main frequency and high frequency energy on the reef flat are higher. In addition, the influence of the distance of the revetment from the reef edge on the water level in front of the revetment is studied. With the increase of the distance, the average water level in front of the revetment increases firstly and then decreases.