Abstract:

The bifurcation sections of Yingpanlu Xiangjian River Crossing Tunnel have superlarge crosssections. The bifurcation sections, located in complex geological conditions, are excavated by double side drift method. The conventional lining construction method can not meet the requirements to ensure the safety of the tunnel construction and the primary support.Therefore, a new lining construction technology, that is, installing the secondary lining by means of special lining formwork jumbos and full scaffold system while keeping the temporary support in place, is adopted.In the paper, the new lining construction technology is presented and the key points of the technology are expounded.The practice demonstrates that the new lining construction technology adopted is effective.

Key words: underwater tunnel, superlarge crosssection, bifurcation section, large span, lining