The southeastern coast of Hainan Island presents harsh conditions for harbor construction,with the stability of breakwaters posing a critical challenge.How to ensure the safety of breakwater structures in high-wave areas is pivotal for the success of the project.Based on the Wanning Emergency Salvage and Comprehensive Base Project in Hainan,this paper utilizes three methods—normative formulas,wave section model tests,and overall wave physical model tests to determine the stable weight of T-shaped blocks on a sloping breakwater and validate the breakwater’s stability.The research findings reveal that the stable weight of the T-shaped blocks determined by normative formulas and wave section model tests is significantly lower than that determined by overall wave physical model tests.The main reason is that the overall wave physical model tests effectively reverse the locally concentrated wave energy effects along the embankment,causing a localized increase in wave height which necessitates a 79% increase in the stable weight of the T-shaped blocks on the breakwater’s protective face.Therefore,for regions experiencing the impact of oblique waves in strong wave areas,it is of great significance to conduct overall wave physical model tests to verify breakwater stability for ensuring design safety. The research results can provide reference for the design of breakwater engineering subjected to oblique strong wave action.