Building foundations for Top-Down construction require a special setting, because the foundations have to be placed way before excavation for the substructure of main building. Usually, the foundation goes into the layer of rock and it is often called...
Building foundations for Top-Down construction require a special setting, because the foundations have to be placed way before excavation for the substructure of main building. Usually, the foundation goes into the layer of rock and it is often called rock-pier foundation. Currently, a cage of steel reinforcing bars is inserted to the pre-excavated hole in the rock layer, hanging down from the wide flange steel column above. This paper presents a new method for connecting the prefounded column and the steel cage with a coupler for better connection between the two. The use of a circular Concrete Filled Tube (CFT) as a prefounded column makes it possible to have this type of connection. The details of the connection and application to a Top-Down construction site is also included in this paper.