Cross passage construction – King George Square

Cross passages are regularly spaced passages between tunnels to provide emergency access underground in the operational rail tunnel. The permanent passages connect the two tunnels and are located every 240 metres along the tunnel alignment.
 

Work details

The methodology used to excavate the cross passage will depend on ground conditions encountered within the tunnel and may involve traditional excavation techniques or controlled blasting.

Work to construct the cross passage will involve:

• Installing rock anchor supports on both sides of the two tunnels, including steel work, drilling and saw cutting
• Excavating the cross passage using traditional excavation techniques or a controlled blasting
  method
• Installing steel mesh, concrete and a waterproof concrete lining in the cross passages and
  surrounding area.

Please see map below for location of the cross passage.
 

Work hours

Construction of cross passages is undertaken 24 hours, 7 days a week. The cross passage will take up to
4-6 weeks to complete, ground conditions permitting.
 

Controlled blasting

If required, controlled blasting will be carried out between 7:30am and 4:30pm, Monday to Saturday. Blasts will not take place on Sundays or public holidays.

Residents and businesses within approximately 200 metres of the blasting area may hear and feel the controlled blast.

Nearby residents and businesses will be notified at least 48 hours’ ahead of controlled blasting.

An SMS alert will be issued 4 hours prior to controlled blasting. Scan the QR code to register to receive SMS alerts, or send your name and mobile number to
[email protected] (message and data rates may apply).