Construction equipment manufacturer Sandvik is awarded a contract to supply 12 of the 19 roadheaders needed for excavation of the twin tunnels of the NorthConnex highway project in Sydney, Australia.
The order – by the Lend Lease/Bouygues joint venture (LLB JV) responsible for delivering the A$2.6 billion (€1.9 billion) construction contract – is the largest single order for Sandvik tunnelling roadheaders since the Sochi Winter Olympics Park excavation more than five years ago. Six new MT720 units and five new MT520 units will be supplied, in addition to an MT620 unit that Bouygues will use from its existing fleet of vehicles.
Phil Marshall, Tunnelling Plant Manager for the LLB JV, said the decision to engage Sandvik for supply of the majority of the machines had been driven by the company’s reputation for delivering high-performance equipment coupled with a previously existing good working relationship between the contractor and the supplier.
The NorthConnex project involves construction of a 9km long all-underground twin tunnel link between the M1 Pacific Highway at Wahroonga and the Hills M2 Highway at West Pennant Falls in the north-west of Sydney.
In July 2012, Transport New South Wales – the State Government’s highways authority – received an unsolicited proposal from private highway operator Transurban to construct NorthConnex, then known as the M2-F3 Link. The route had already been designated as Sydney’s second most strategically important highway project after WestConnex. Transurban already operates a tolled 21km section of the M2 highway close to the NorthConnex link, as well as the 3.6km Lane Cove Tunnel which it acquired from Connector Motorways for A$630 million in 2010 after the latter went into receivership.
Roadheader and surface miners are specified as the main construction method on account of an engineering design that incorporates different internal tunnel profiles at various locations along the alignment. Broadly speaking, each tunnel will incorporate three lanes of traffic across a profile of approximately 14m wide x 8m high. In addition to the main 9km tunnels there will be two underground ramped interchanges at both the northern (M1) and southern (M2) end. At the northern end of this will facilitate direct east-west access to the local road network in addition to continuous access to the north-running M1 itself. At the southern end of the alignment the ramped interchanges will facilitate access to the north-south running local road network in addition to direct access the east-west M2.
A tunnel excavation period of 32 months is scheduled, beginning this month (July 2015) and based on an expected project advance rate of 25-30m/week. Completion of the finished lining, M&E fit out and tunnel ventilation is scheduled for the first quarter of 2019 ahead of testing, commissioning and final opening by the last quarter of the same year.
At 90m deep in some places, the NorthConnex tunnels will be the deepest in Sydney. More than half of the alignment is at a depth of 60m, and at 9km long they will be the longest highway tunnels in Australia.
Philippe Bonnave, Deputy Chief Executive of Bouygues Construction, said: “This construction contract is further proof of our ability to meet major technical challenges and to carry out large-scale infrastructure projects in Australia in partnership with well-established local contractors. NorthConnex is a project with a high environmental value, which will relieve the suburbs of Sydney of motorway traffic congestion while conserving natural spaces.”
The A$3 billion NorthConnex project is being funded by a mix of future toll income and contributions of up to a total of A$810 million by the State and Federal Governments. The alignment broadly follows Pennant Hills Road and is expected to move 5,000 heavy goods vehicle movements/day from Pennant Hills Road, and cut 15 minutes off journey times for all traffic that makes the switch.