Since March 15, Catherine has begun her work. The tunnel boring machine will have the task of digging the tunnel for the West/East tram line, between Rue Ségurane (the entry shaft) and Rue de France at the corner of Boulevard Grosso.
It measures nearly 78 meters in length, weighs 1,400 tons, and has a diameter of 9.68 meters. Catherine, the tunnel boring machine christened last January by Christian Estrosi, deputy mayor of Nice, is a technological monster.
A Colossus Just Beneath Our Feet
The most imposing part of this machine is surely the shield. It includes the 130-ton cutting wheel fixed at the front that allows it to dig. It also comprises the crusher and the propulsion cylinders to move this gigantic machine forward.
At the rear, we find the trailers. Installed on these are the control cabin and all the equipment necessary for the construction work: hydraulic networks, 5,000 kW electrical installations, and ventilation. There are also gas detectors, fire extinguishers, and automatic sprinklers in case of fire.
The tunnel boring machine advances at a rate of 10 meters per day, 24/7 for 6 days. Catherine began her work in March and is expected to continue until February 2017.
A somewhat discreet colossus since it is currently located beneath Place Garibaldi. “We wanted a work tool that causes the least possible nuisance to the locals,” says Christian Estrosi. For now, he is holding up his end of the bargain.
Optimal Treatment of Excavated Material
And for those wondering what the imposing installations at Quai Cassini are used for… they are used for the treatment of the excavated material from the tunnel boring machine. Thanks to a piping system, everything expelled by Catherine goes directly to the port and is then shipped on boats. These are subsequently evacuated to Fos-sur-Mer to be unloaded and revalorized.
And again, less inconvenience for the locals since no trucks will circulate in the area to transport these materials.
However, the assembly of the tunnel boring machine is not quite complete. It will be finished by the end of April with the installation of the third trailer.
