Abstract
Taking the Mawan Cross-sea Channel Project as an example, this paper introduces the synchronous construction technology for roads in shield tunnel sections. This technology employs internal construction control measures, integrates prefabrication with cast-in-place construction, and achieves synchronous flow construction of structural surfaces, thereby better aligning with overall construction continuity. In structural construction, precast box-type members are adopted for the middle-span lane slabs, which not only avoids the construction difficulties associated with cast-in-place middle-span lane slabs but also facilitates the transportation and installation of precast components through a novel hoisting and transport method. The paper elaborates on the control measures implemented during the construction process, which satisfy construction safety conditions. For curved slabs, a steel formwork turnover process is employed, which, compared with conventional timber formwork construction, significantly accelerates formwork installation and removal, thereby effectively enhancing construction efficiency and reducing the construction schedule. The side lane slabs, crash barriers, and pavement slabs all utilize cast-in-place processes. This construction mode combining prefabrication and cast-in-place methods can serve as a reference for future similar projects.
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Preamble
Synchronous Road Construction Technology for the Shield Section of the Mawan Cross-Sea Tunnel
Yu Yue¹
¹Shanghai Tunnel Engineering Co., Ltd., Shanghai 200000, China
Abstract
This paper presents a synchronous road construction technology for the shield tunnel section of the Mawan Cross-Sea Tunnel project. By implementing internal construction control measures that integrate prefabricated and cast-in-place methods, the approach achieves synchronized flow construction of structural surfaces while enhancing overall construction continuity. The middle-span lane slabs employ prefabricated box elements, which not only avoid the construction difficulties of cast-in-place middle-span slabs but also facilitate efficient transportation and installation through an innovative hoisting and barge-transportation method. The paper elaborates on the control measures implemented during construction to satisfy safety requirements. For the arc-shaped slabs, a steel formwork flipping process is adopted, which significantly accelerates formwork erection and removal compared to conventional timber formwork, thereby effectively improving construction efficiency and reducing construction time. The side lane slabs, crash barriers, and road surface slabs are all constructed using cast-in-place methods. This hybrid construction model, combining prefabrication and cast-in-place techniques, can serve as a valuable reference for similar future projects.
Keywords: shield tunnel; synchronous construction; control measures