Martina (tunnel boring machine)

The Martina tunnel boring machine (officially named as the S-574.^[2]) is a hard rock tunnel boring machine built by Herrenknecht AG. It is the largest hard rock tunnel boring machine in the world and has been used for drilling the Sparvo Tunnel, a part of the larger Variante di Valico project in Italy.^[3]

Martina (tunnel boring machine)

Class overview
Name	Martina
Builders	Herrenknecht AG
Operators	Italy
Cost	US$60 million (2011) (equivalent to US$80.2 million in 2023)[1]
In service	2011-2013
Completed	1
Retired	1
History
Italy
Name	Martina
Builder	Herrenknecht AG
Commissioned	August 2011[2]
Fate	Disassembled after July 29, 2013[2]
Notes	The largest hard rock tunnel boring machine ever built
General characteristics
Class & type	S-574-type Tunnel boring machine
Tonnage	4,500 tonnes (4,400 long tons; 5,000 short tons)
Length	130 metres (430 ft)
Beam	15.62-metre-diameter (51.2 ft)
Installed power	Total: 18 MW (24,138.4 hp)

Specifications and operations

The Martina cost 60 million USD,^[4] has a shield diameter of 15.55 metres, an excavation diameter of 15.62 metres, a length of 130 metres, a total weight of 4500 tonnes and an annual operating consumption of 62 million kWh. The cutterhead required 12,000 kW of power whilst the overall vehicle requires 18 MW total installed capacity to function.^[2][4] The machine started work on the Sparvo tunnel in 2011, with drilling of the 2430-metre north tube completed in 2012. The drilling of the 2600-metre south tube was finished in 2013, bringing the 5-kilometre tunneling project to an end.^[5][6][7]

See also

• List of longest tunnels
• List of long tunnels by type
• List of mining companies