Owing to long exposure to the urban environment, the construction technology of the enclosure structure is closely related to the urban low-carbon development. Shenzhen Metro has recently proposed a novel prefabricated enclosure structure and demonstrated its application. Among them, the mechanical properties of the beam-wall joint between precast diagram wall and precast beam are the core for the performance of the prefabricated enclosure structure. This study demonstrated foremost the application of prefabricated enclosure structure and its key joint mechanical model in Shenzhen Metro Phase V stations. First, this study conducted a full-scale bending experimental study on beam-wall joints and continuous joints. Second, the Joint Coordinating Contact Model (JCCM) of the beam-wall joint was proposed. Third, the model was validated and assessed by using the experiment data. The main conclusions include: (1) The beam-wall joint showed semi-rigid properties despite using reliable assembly. (2) The performance degradation of the beam-wall joint originated from the interface. The interface weak link changed the solid continuity of the joint. (3) With reasonable rebar splices (≥66%), the joint stiffness does not change substantially. However, the joint performance with too few rebar splice showed significant degradation (≤33%). (4) JCCM assessment suggested a rigid beam-wall joint by enlarging the joint height by 31.3% and using 44% rebar splice ratio. The research achievement provides a theoretical basis and application value for the assessment of beam-wall joints and the promotion of prefabricated enclosure structures.