West Gate Tunnel Project – Northern Portal

Overview of Project

The initial works on the main Northern Portal at the West Gate Tunnel Project were completed, enabling the TBMs to be lowered into the dive structure and assembled before tunnelling beneath the West Gate Freeway. These works, commencing in March 2020, involved multiple crews working staggered 24/7 shifts. In just over six weeks, the team installed over 2,000 tons of reinforcement and 13,000m³ of concrete—ahead of schedule. The scope of work included:

• Placing and finishing 4,500m² of blinding concrete.
• Six weeks of 24/7 operations.
• Steel fixing 2,100 tons of reinforcement.
• Forming, placing, and finishing approximately 4,500m² of structural walls and slabs up to 2m deep, totalling over 9,100m³.
• Forming 900m² of single-sided wall formwork (1m thick, 7m high), steel fixing, and pouring.
• Forming, steel fixing, and pouring a head wall measuring 41m wide, 21m high, and 2.4m thick.