Objective Developing offshore photovoltaic systems is an effective approach to overcome land constraints. However, the wave run-up phenomenon on their pile foundations in the complex marine environment affects the stability of supporting structures and the safety of PV modules. Therefore, investigating the wave run-up characteristics of pile foundations under different group pile arrangements holds significant guiding value for the practical engineering layout of group piles.

Method A numerical model for the interaction between pile groups and waves was established, and the accuracy of the constructed model was verified using existing data. Based on this established model, the wave run-up effect on pile foundations at different positions was investigated, and further analysis was conducted on the influence of different foundation arrangement forms on wave run-up.

Result Studies have shown that along the wave propagation direction, the wave run-up heights of front and rear pile foundations exhibit a significant shielding effect. Taking a group of four piles arranged in a tandem configuration as an example, the wave run-up of the first pile is slightly higher than that of a single pile due to the blocking effect of the subsequent piles. For the latter three piles, the wave run-up in front of each pile decreases sequentially, which is attributed to factors such as energy attenuation. On the leeward side of the piles, the wave run-up law is more complex than that of the wave run-up on the windward side, owing to the phase interference between incident waves and diffracted waves, and the run-up height does not decrease in sequence. When the pile spacing is reduced, the shielding effect of the pile group becomes more pronounced.

Conclusion The numerical model established and the analysis of the wave run-up laws of pile foundations in this study can provide certain references for practical engineering design.