TERRATEC is celebrating the delivery of the first of two new tunnel boring machines (TBMs) that will excavate the Río Subterráneo a Lomas tunnel in Buenos Aires, Argentina, following successful factory acceptance testing last week.
The 4.66-m diameter TERRATEC earth pressure balance machine (EPBM) will be deployed by Italian contractor CMC di Ravenna on a 13.5-km tunnel that will carry drinking water from the newly expanded General Belgrano Water Treatment Plant, in the city of Bernal (Quilmes district), to the city of Lomas de Zamora.
The tunnel is a key component of the multi-billion-dollar Agua Sur system that is currently being built by Argentina’s national water and sanitation company AySA. Financed by the Government and the Development Bank of Latin America (CAF), it is the country’s largest water infrastructure project in 40 years and will provide access to fresh water for 4 million inhabitants in the southern metropolitan area of Buenos Aires.
The 4.66-m diameter TERRATEC EPBM has been designed to tackle the variable soft ground geology along the project alignment, which ranges from silts to sandy silts with some cobbles expected. The TBM’s high-torque, soft-ground cutterhead features a spoke style design with a 49% opening ratio and cutting tools consisting of fixed and back-loading knife bits to ensure rapid advancement and minimum interventions.
The tunnel will be excavated at an average depth of 25 m, beginning with an approximately 400-m radius curve and continuing along an essentially straight alignment, reaching a maximum slope of +/- 2.0%. As the machine progresses, it will install a precast concrete segmental lining ring consisting of six (four parallelograms and two keys) 250-mm thick, 1,400-mm wide, segments.
“From the initial concept to this point in the process it has been refreshing working with TERRATEC. They have listened to our requests and, as a result, we have just accepted a machine that we are all sure will do a good job,” says Ezio Collinelli of CMC di Ravenna. “The TBM will arrive on site on time thanks to efficient production on TERRATEC’s part and our project team is looking forward to working with the TERRATEC field service support team.”
In recent years, TERRATEC’s order book has demonstrated significant growth around the world. Machine performance and client satisfaction have provided the foundations of a loyal customer base and are making the Australian manufacturer the first choice for more and more contractors.
Last year, TERRATEC opened a new large-diameter TBM facility that has delivered more than 12 new machines in the second half of 2017 and beginning of 2018.