Abstract: Field investigations are carried out to analyze armor block displacements caused by typhoon events, with a focus on characterizing the spatial distribution patterns of dislocated blocks. Utilizing measured wave data and satellite imagery, the stability of armor blocks is assessed, and representative typhoon cases are identified. A storm-wave coupled model, forced by the ERA5 wind field, is employed to simulate storm surge and wave evolution in the seawall foreshore. Furthermore, a parametric approach is developed by integrating the armor block stability weight formula with parameter optimization techniques. The feasibility of each parametric method is systematically evaluated against field-observed block stability conditions. The research results indicate that the instability probability of armor blocks along the transverse direction of the seawall follows a normal distribution. The storm-wave coupled model driven by the ERA5 wind field effectively reproduces the generation and the development of storm surges and waves in the foreshore zone. Notably, armor block damage can occur even under relatively low wave heights if wave periods are sufficiently long, suggesting that wave period effects should be incorporated into stability formulations for open-coast applications. The parametric method based on the Soviet standard formula, when combined with the H₄% wave height parameter, achieves an agreement level of 83% with field observations, indicating its improved suitability for estimating the armor block stability weight under typhoon conditions.