The settlement calculation of soft foundation under seawall reinforced by semi-rigid piles is mainly based on the composite foundation calculation method.In order to compare the difference between the calculation results of the composite index calculation method and the solid pile method,combined with an engineering example of a sloping seawall,taking the geotechnical finite element software PLAXIS 3D as the analysis platform,we respectively used solid piles and composite indexes to establish the spatial elastoplastic finite element model for the stability analysis of cement mixing piles on the sea embankment soft foundation.The results show that the solid pile model can simulate the soil arch effect,settlement difference between pile and soil in the plane of pile head,and the constraint effect of cement mixing pile on soil between piles,and reflect the displacement and stress distribution of soft soil foundation more truly.The analysis results provide reference for similar engineering and numerical simulation calculation of soft foundation reinforced by semi-rigid piles.