<p>The construction deviations of super-long span bridges in high-speed railways during the construction phase directly affect the track smoothness after bridge completion, thereby impacting the operational quality of high-speed trains. This study analyzes the main influencing factors of smoothness control in super-long span bridge construction based on their technical characteristics, proposes a construction-phase bridge smoothness control strategy combining segmental assembly control with holistic assessment and adjustment, and investigates smoothness control methods during segmental assembly using the virtual chord measurement method, supported by case studies. The research demonstrates that implementing smoothness control during construction is essential to ensure post-completion track smoothness of super-long span bridges. The proposed strategy effectively translates smoothness control objectives into key construction phases. The virtual chord measurement method proves highly operable and effective for segmental assembly smoothness control. Post-completion multidimensional evaluations using chord measurement and other techniques can guide track smoothness adjustments. Conducting construction-phase smoothness control for super-long span bridges lays the foundation for achieving high track smoothness objectives on high-speed railway bridges.</p>