Shafts serve as the gateways to the underground, and their design and construction are crucial for the successful completion of any tunneling project. Every tunnel necessitates the construction of two shafts: the launching shaft and the receiving shaft.

• Launching Shaft: Primarily utilized to set up the tunneling equipment, the launching shaft is considered the starting point of the tunneling process.
• Receiving Shaft: Employed for machine head recovery upon the completion of the crossing, the receiving shaft is regarded as the endpoint.

The method of shaft construction varies based on different parameters, including:

• Shaft diameter
• Shaft depth
• Ground nature
• Presence of the water table

STCC has implemented the construction of high-quality shafts using various methods. The following are the construction methods employed for shaft construction:

• Sheet piles
• Cement block method
• Bored cast-in-situ secant piles
• Caisson/ sinking method