Due to the rapid development of the Taiwanese economy, quality of life is continually improving. Installing extra-high voltage cables in underground tunnels to meet the increased electricity needs of urbanization and modernization is the current trend. In recent years, shield tunneling has become the main underground tunneling method for metropolitan areas because it is safe, avoids the need for ground excavation, does not affect ground transportation, does not hinder the flow of groundwater, and has a low environmental impact. This paper used the Taiwan Power Company’s “Fenglin 2nd Road Shield Tunnel Turn-Key Project of the 345kV Underground Cable Route Connecting Gaogang, Wujia, and Kaohsiung” as a case study site. It has geological properties as high water table, sandy soil, and gravel formations. This paper also introduced the construction experiences of this project, including considering the work safety of launching vertical shaft excavation, designing a divergent shaft to place directly above the shield tunnel, constructing a large-diameter, sharp-curved shield tunnel, revising the project’s management items and procedures, and pipejacking a connection adit.
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