The steel platform structure consist of 3 floors have been made in the basement of the air shaft to accelerate the NATM excavation works at the Sirkeci station in 50 m depth.

The aim of platform is to provide working area for the machines to excavate 3 tunnels gradually. The platform’s connections have been designed bolted to provide easy disassembly after the end of excavation at each floor.

The project has been completed in a very short time as 17 days due to the importance of time.

The plan layout has been considered by the most negative measurements for each floor  in the design. The contour line of construction is designed by chamfered profiles due to the various conditions of shaft walls shotcrete surface. The structure is designed according to the very heavy loads (9 ton/m2) occuring during the excavation.  Heavy load bearing gratings is used for the deck.