Research on Arrival-Departure Track Design Optimization for Express/Local Train Lines

Objective As a critical infrastructure for express/local train operation, the arrival-departure track rational design directly impacts operational efficiency and engineering investment returns. Given current issues in China′s express/local lines—including mismatches between track configurations and functional requirements, and imbalances between engineering scale and operational outcomes, it is imperative to conduct refined researches on arrival-departure track selection and engineering design. Method Through case analysis method, the applicable scenarios of four typical track configurations are systematically examined, including twin-island four-track（with inner/outer main lines）, single-island four-track, and bilateral four-track. By employing technical-economic comparison methods and combining CBTC signaling system characteristics, a dynamic optimization model for effective track length is proposed. And by using traction calculation simulations, the impact of different turnout types selection on operational efficiency is quantitatively analyzed. Result ＆ Conclusion It is proposed that selecting track configurations should be based on core operational requirements including express train overtaking, local train holding, and transfer between express/local trains. The effective length of arrival-departure tracks should be determined by comprehensive evaluation of conventional safety clearances, zero-clearance operations, safety sidings, and unidirectional operations. Turnout type selection should integrate factors such as section running time, passenger comfort, and civil engineering scale. Validated with practical engineering cases, this method significantly improves the alignment between arrival-departure track design and operational demands.