在兰渝铁路黑山隧道出口湿陷性黄土浅埋段下穿民居施工中，综合考虑湿陷性黄土的变形特性，以控制地表沉降变形、保证施工安全为主要目的，采用中管棚配合小导管超前预支护，使用双侧壁导坑法开挖，加密型钢架加强支护，通过围岩监控量测动态调整支护参数，并配套采取初期支护增设套拱、初期支护喷射混凝土变更为模筑(吊模)C45混凝土、增设锁拱锚管等措施，安全顺利通过下穿民居段。

The exit section of Heishan tunnel on LanzhouChongqing railway runs in wet subsidence loess and beneath residential area with shallow cover. Advance reinforcement by mediumdiameter pipe roof and smalldiameter pipes, excavation by double side drift method, reinforcement by closelyspaced steel ribs, monitoring and reinforcement parameters adjustment, as well as assistant primary reinforcement such as cooperated arch and castinsitu C45 concrete and arch foot anchoring pipes, are executed. In the end, the tunnel passes underneath the residential area successfully.