Wave-seabed-structure interaction has become one of the main concerns of coastal engineering and researchers, as it may largely affect the seabed instability and structure safety. In this study, a series of experiments have been carried out in a wave flume to investigate the wave motion and wave-driven pore pressure around a submerged impermeable breakwater as well as without the breakwater. Pore pressure within the sandy bed and water surface elevation are measured simultaneously during the laboratory experiments, which are used to investigate the effects of wave height, wave period and breakwater structure on the wave-seabed-structure interactions at different water depths. The experimental results of two different constraint conditions (around a submerged impermeable breakwater as well as without the breakwater) are compared to show that the interaction of water waves and a submerged breakwater cause a significant change of wave motion and wave-induced pore pressure within the sandy bed. Meanwhile, it is found that the values of pore pressure along both the wave propagation direction and vertical seabed depth are largely dependent on the water depth.
With the rapid development of coastal management strategies in the last few decades, offshore structures such as breakwaters are commonly constructed for protecting the coastal environment, also offshore breakwater are becoming common feature of deepwater ports. Like other marine structures, submerged impermeable breakwaters may be affected by the strong interaction of wave-seabed-structure.
