Design and application of a deep excavation adjacent to large-diameter pipes

The Shanghai Caoxi Road Station Plot Public Open Space Project is located in the downtown of Shanghai City. The excavation is adjacent to several city roads, pipelines, elevated road, light rail line and station. Protection requirements of the surrounding facilities are quite high, especially for the large-diameter sewage pipes at the north side of the excavation. The general situation of the project and the overall design scheme of the deep excavation are introduced. Emphasis is put on the technical countermeasures of protecting the large-diameter sewage pipes, including constructing the bored piles in the cement mixing soil, using elevated soil conveying path, and tracing grouting. The monitoring results show that the surrounding environments are effectively protected by the adopted supporting system and technical countermeasures. The successful construction of the deep excavation creats favorable conditions for the construction of the main structures of the project.