Abstract: To realize the complete life cycle of railway tunnel in green and lowcarbon development, a case study is conducted on the Qinghuayuan tunnel, the New Badaling tunnel, and the Badaling Great Wall station, data statistical analysis is conducted to assess the railway tunnel construction and operation stage of carbon emissions. The authors propose tunnel carbon reduction design strategy from the aspects of tunnel line, station selection, construction, structure, ventilation, and lighting. Research results show that the carbon reduction design strategy mainly involves increasing carbon sink and reducing carbon emission. Carbon sink can be increased by (1) reducing the surface land occupation and increasing the surface green area; (2) adopting green retaining wall and green vegetation cover for the tunnel entrance to increase the carbon sink capacity. Carbon emission can be reduced by (1) reasonably selecting tunnel line and station to minimize passenger traffic connection; (2) reducing the amount of earthwork excavation and support measures using the station tunnel design scheme; (3) designing concept and method of surrounding rock selfbearing tunnel to reduce the amount of lining concrete; (4) adopting airfree piston ventilation system, intelligent management of lighting system, elevator, and other large equipment for the underground station to reduce the energy consumption in the operation stage. Finally, the future green construction technologies of railways, such as the construction of green structures, the research and development of fully prefabricated and exquisite structures, the intelligent management and control technology of equipment, the railway strip photovoltaic power plant, and the compressed air energy storage power station, are proposed.

Key words: railway tunnel, lowcarbon design, green construction, carbon emission reduction