In the interaction between waves and semi-submersible platforms,waves can climb along the platform columns and exert impact loads on them.In extreme cases,waves may even strike the platform's lower deck,posing a severe safety risk.Therefore,accurately predicting wave-induced uplift and slamming effects on the platform is of great significance for its design.In this study,based on the meshless particle solver MPSGPU-SJTU,the numerical simulation of the semi-submersible platform under the action of waves was carried out,the MPS(moving particle semi-implicit)and GPU(graphics processing unit)parallel acceleration technology was utilized to numerically investigate the behavior of fixed semi-submersible platforms under wave action.Numerical simulations were conducted to analyze wave-induced uplift and slamming phenomena for fixed semi-submersible platforms subjected to regular waves with three different wave heights.As the wave height increased,more areas of the platform's lower deck were subjected to wave slamming,and the peak pressures at the pressure measurement points on the platform also increased accordingly.