关键词: 葛洲坝大厦, 深基坑, 支护设计

Abstract: The Gezhouba Building is located at urban area of Hankou. The excavation depth for the building is between 16.5 and 20.1 meters with a footprint area of approximately 2500 square meters. The shape of the excavation is an irregular rectangular. Due to its depth, this excavation in the urban area with strict environmental constraint belongs to a super deep category. Therefore, it is necessary to select an appropriate excavation supporting method that is most suitable for the subsurface conditions, meeting the safety requirement, having a good constructability and importantly, being cost effective. It is anticipated that the artesian layer will be encountered during the excavation; therefore, the dewatering design is also required for the construction.  Since the soldier pile with rake supporting is a relatively matured technique, the general deep excavation scheme for this project is following: sloping the area to be excavated; castinplace reinforced concrete pile with reinforced concrete raking as supporting system. Jet grout columns as seepage cutoff curtain and as bottom artesian groundwater sealoff with pointwell dewatering system in the middle of the excavated area; soil nailed wall with wire mesh and shotcrete for the slope surface protection. The construction indicates that this supporting scheme is satisfactory.

Key words: Gezhouba Building, Deep Excavation, Supporting Design