Herrenknecht supplies first TBM for Metro construction in Rio de Janeiro
Herrenknecht AG is supplying a tunnel boring machine with a diameter of 11.46 meters for the construction of the new metro line 4 in Rio de Janeiro. It will contribute to relieving the traffic routes in the metropolitan area. At the company’s headquarters in southern German Schwanau the first tunnel boring machine to be used in Rio de Janeiro was accepted by the customer in late September 2012. During the workshop acceptance Regis Velasco Fichtner Pereira, Secretary of State of the state of Rio de Janeiro, presented the project to the Brazilian media representatives in attendance.
Schwanau, Germany, September 27, 2012. The »Cariocas«, the inhabitants of Rio de Janeiro, have some eventful years ahead of them. In 2014, Brazil hosts the soccer World Cup. Two years later, in 2016, the Summer Olympics are in Rio de Janeiro. In between, in 2015, the 450th Birthday of the city will be celebrated The state government of Rio de Janeiro is investing in a range of infrastructure projects to improve the traffic situation for the approximately eleven million inhabitants of the metropolitan area, and for the expected guests. One major project is the construction of the new Metro Line 4, with a total length of 14 kilometers.
Herrenknecht is supplying a tunnel boring machine with an EPB shield (Ø 11.46 meters) for the 4.6 kilometer long section of the new Line 4 between the stations »Gavea« and »General Osorio«. On September 27, in the presence of the representative of the state government of Rio de Janeiro, State Secretary Velasco Regis Fichtner Pereira, the acceptance of the machine by the customer took place at the Herrenknecht plant in Schwanau. The customer is the »Consórcio Linha 4 Sul«, consisting of the Brazilian construction companies Construtora Norberto Odebrecht S.A., Construtora Queiroz Galvao S.A. and Carioca Christiani Nielsen Engenharia S.A. For the second largest city in Brazil, it is a first: for the first time a tunnel boring machine is being used, after all previous tunnels were built conventionally or as cut-and-cover tunnels. To ensure the machine can cope with the different ground conditions along the tunnel route, the Herrenknecht engineers designed it so it can be converted in the tunnel. Herrenknecht project manager Carlos Manzano Rey explains: "It is planned that the machine will cover the first 300 meters in open mode, then be converted for about 3,000 meters in closed EPB mode. Finally, around 1,300 meters will again be tunnelled in open mode." In open mode, the firm hard rock (gneiss) is transported away on a conveyor belt. In closed EPB mode removal is handled by a screw conveyor whose conveying speed simultaneously safely and precisely regulates the face support pressure during excavation in the predominantly sandy soil. Another special feature of the machine for Rio de Janeiro's Metro Line 4 is the articulation in a diameter range of more than eleven meters. It will allow the tunnelling team to cope with the tight bends with a radius of just 250 meters in some cases.