Brief
Design & Install a suspended access stairs which can be progressively extended down the shaft as it is being excavated, to provide a continuous means of egress during the shaft excavation and subsequently a means of emergency egress during the tunnelling works. The scope of works included the design, fabrication and installation of the suspension beam system. The installation methodology allowed pre-assembled stair tower modules to be lowered by crane and connected to the base of the hanging stairs to minimise the outage time and avoid any interruption to program continuity.

Features

• 85m high stair tower suspended from cantilevered steel beams at the top of the shaft
• Capacity for up to 40 persons on the stairs in the event of an emergency evacuation
• Stair modules pre-assembled above ground and craned into position for rapid connection
• Out-of-service duration limited to one hour.