Abstract:  Rail transport engineering that is safe, reliable, and costeffective is a developing trend in the rail transit system. In this study, key technologies in designing the fire hydrant system of the NanjingMa′anshan intercity railway and its advantages over conventional designs are introduced. Initially, through interpreting relevant codes and analyzing engineering experience, a principle of "pump room protection distance for fire hydrants within 2 000 m" and a fire water supply scheme termed "multischeme water supply combination mode in case of fire" are proposed. The specific contents include the following: (1) Scheme I, where two adjacent stations are responsible for the half sections ahead of and behind the stations, is prioritized. (2) For section lengths less than 2 000 m, Scheme II can be adopted, wherein one station is responsible for the entire singleline section between two stations. (3) For sections more than 4 000 m, an independent fire pump room should be established at the ventilation shaft based on Scheme I to ensure that the protection distance of all fire pump rooms is within 2 000 m. (4) Each fire pump room′s water supply units should be fully segregated. Subsequently, two innovative firefighting water supply schemes for singlewater source viaduct stations are proposed: the outdoor lowvoltage and indoor temporary highvoltage system for viaduct stations adjacent to municipal roads and near cities with robust firefighting infrastructure; and the indoor and outdoor temporary highvoltage system for those in the middle of municipal roads and distant from cities with inadequate firefighting infrastructure. Lastly, a layout principle for fire infrastructures, such as outdoor fire water tanks and hydrants for viaduct stations, is proposed. It is recommended that for the outdoor lowvoltage and indoor temporary highvoltage system, water tanks should be positioned if the distance between the viaduct station and the tank exceeds 150 m; fire hydrants should be strategically placed at the entrances and exits of viaduct stations.

Key words: rail transit engineering, fire hydrant system, pump room protection distance for fire hydrant, multischeme water supply combination mode in case of fire, station water supply pressure system, outdoor fire water tank