下穿水域的盾构铁路隧道具有难以设置辅助坑道的特点，为解决疏散救援紧急出口（避难所）短缺的难题，在调研总结现有典型水下盾构铁路隧道工程实际的基础上，结合人员在狭长空间及楼梯的疏散心理，采用理论分析等方法，形成水下铁路盾构隧道疏散救援模式、底部疏散廊道及竖井式紧急出口分级设计等内容。研究结论如下： 1）隧道长度超过20 km应考虑火灾，并设置紧急救援站；长度小于20 km以应对列车故障为主，采用竖向疏散模式；在底部疏散廊道功能设计、紧急出口（避难所）数量等方面，应结合隧道长度、下穿水域的盾构段长度、水域段长度分级设计。2）为保证人员长距离疏散的安全感，建议环境照度≥40 Lx，形成不通行救援车辆和通行救援车辆2种情况下，底部疏散廊道横断面及避难区长度设计方法。3）基于人员在黑暗狭长空间及楼梯的疏散心理，制定竖井式紧急出口分级标准，提出扶梯、直梯等疏散辅助设施分级设置标准及每间隔10 m高差增设休息平台的建议。

There is a lack of sufficient emergency exits (shelters) for disaster prevention, evacuation and rescue, because it is difficult to construct shafts for underwater railway shield tunnels. To address this challenge, the designs of typical underwater railway shield tunnels is summarized firstly. Then, the evacuation and rescue modes are classified, and the hierarchical standards of under-rail evacuation walkway and emergency exits with vertical shaft are specified, based on the evacuation psychology in confined spaces and staircases. Findings are as follows: (1) Emergency rescue stations should be established for tunnels exceeding 20 km in length to deal with tunnel fires, while vertical evacuation modes should be adopted for tunnels under 20 km to deal with the non-fire accidents. The functional design of under-rail evacuation walkway and the quantity of emergency exits with vertical shaft require graded design based on tunnel length, underwater shield section length, and water section length. (2) It is recommended that the ambient illumination be ≥ 40 Lx, to ensure the safety of longdistance evacuation. In addition, the design methods for the cross-section and length of under-rail evacuation walkway are established for both non passing and passing rescue vehicles. (3) The classified standards for emergency exit with vertical shaft and evacuation auxiliary facilities, including escalators and straight ladders are proposed. Meanwhile, the rest platform is suggested to add every 10 m of height difference, considering evacuation psychology in dark confined spaces and stairwells.