McKinnon Realignment
BACKGROUND

The Victorian Government has set out to remove fifty street-level crossings on Melbourne’s metropolitan rail network to improve safety and efficiency. The level crossings at North Road Ormond, McKinnon Rd McKinnon and Centre Rd Bentleigh are part of the first level crossing removal project to achieve this goal. These projects removed the level crossings by lowering the rail line below the roads and include the design and construction of new stations, platforms and access improvements to public transport connections.

 

Photos by Daniel Bowen

SCOPE

Lowering the rail lines in a tight existing rail corridor meant that retaining walls had to be constructed with minimal impact on rail operations. In addition to this with the walls being installed through residential areas, it was important to minimize the effect on local residents. Once retaining walls were installed, a short 8 week period was all that was allowed complete the removal of existing rail, excavate the new alignment, finish the walls, construct basement slabs and relay the rail hardware for reopening of the rail line.

OUTCOMES

Steel sheet piles provided a waterproof wall system with minimal wall footprint. Combined with installation using a vibration free Giken Silent Piler the sheet piles walls could be installed with minimal impact on adjoining properties and rail activities.

The Giken piling machine drove piles in very dense sands and gravels silently double shifting 24hrs per day. The narrow working corridor (2.5 -3m) meant that at most only one of three of the rail lines needed to be closed, heavier piling equipment would have required rail closures not available to the contractor.

The supply and delivery of sheet piles to site resulted in a reduction in the number of trucks impacting residents and users of adjacent streets, approximately one-tenth of the number of trucks are required for sheet piles compared to a concrete solution. The sheet piles also provided a clean clear surface upon excavation which reduced the wall finishing time and enabled efforts to be concentrated in other critical areas of the works during the 8-week shut-down.