Abstract: The construction of a new highway overpass bridge imposes significant additional horizontal stresses and displacements on adjacent existing high-speed railway embankments, potentially affecting operational safety. This study evaluates the impact using the Minhou-Pingtan Expressway project crossing the Hangzhou-Shenzhen Line as a case study. Three-dimensional finite element models (Midas GTS NX) simulated bridge piers and railway embankments, while two-dimensional models analyzed deep excavation and support effects. Lizheng Slope software additionally assessed slope stability. Comprehensive analysis confirms the construction impact on the high-speed railway subgrade is controllable, with all displacement and deformation values meeting regulatory requirements.

Key words: Highway Engineering, Overpass Bridge, Cross-Over Construction, Railway Embankment, Numerical Analysis