Abstract: Due to the rapid development of cities, the traffics increased dramatically, which resulted in the development of urban interchanges. In order to minimize the adverse impact on the regional planning, building underground interchanges has become a new trend. The functions, structural design control factors and construction technologies of underground interchanges are presented in the paper, with Xiangjiang Tunnel and Wanshishan Underground Interchange as examples. The paper can provide reference for the design and construction of similar projects in the future.

Key words: tunnel, underground interchange, large span, double arch, small clear spacing