Abstract: In this paper, the existing prefabrication methods of immersed tunnel elements are systematically analyzed and studied, the general process flow of fixed dry dock method, mobile dry dock method, and factory method are discussed, the process characteristics and construction difficulties of each technology are analyzed, and a selection table of precast methods for reinforced concrete elements is proposed. Through indepth investigation of the three methods, differences are obtained. Furthermore, six combinations are constructed regarding the process classification. Based on the comprehensive comparison and selection from multiple perspectives including the novelty, costefficiency, and feasibility, the mature and highcost processes are ruled out, whereas the technology of flat ground flow line prefabrication of element and dynamic water entry is recommended. Finally, the application of the specific case is studied, and the quantitative comparative analysis with the existing process in terms of time limit and cost is conducted. The analytical results show that the process has certain advantages and is worth popularizing.

Key words:  , immersed tunnel, reinforced concrete, element prefabrication, element water entry, process combination, flat flowline prefabrication