Experimental Investigation on Wave Evolution and Seabed Response During the Long-Term Development of Sloping Beach

Abstract Nonlinear wave action plays a crucial role in cross-shore sediment transport, significantly impacting various coastal engineering challenges. This is especially true when assessing beach processes for shore protection methods, demanding precise evaluations. The nonlinearity of waves can instigate near-bed sediment transport. Previous studies mainly focused on the evolution of wave nonlinearity within specific cross-shore profiles, often neglecting the corresponding seabed response. To gain a deeper understanding of hydrodynamics on a sloping beach, we conducted experiments at a small scale within a flume. These experiments aimed to investigate wave evolution and seabed response concerning cross-shore profile development. Over a period of up to 60 hours, we continuously recorded wave heights and analyzed characteristic wave patterns. We also discussed the seabed response at various horizontal positions along the beach. Our findings reveal a reciprocal relationship between cross-shore profiles and wave evolution. In general, wave nonlinearity gradually increases during propagation. However, the nonlinear indicators of waves remain relatively stable over time at the same water depth. Meanwhile, wave-induced seabed responses vary both over time and across different spatial positions. The excess pore pressure within the seabed gradually decreases with increasing depth at various horizontal positions.