Six TBMs to Expand Rome's Metro System
The first of four Herrenknecht TBMs for Line C of the Rome metro officially commenced on 3rd July, 2008 to drive the tunnels starting from the Giardinetti launch box and heading to the city centre. The line is built by Metro C SpA, whose partners are Astaldi, Vianini Lavori, CMB, Ansaldo TSF and Consorzio Cooperative Costruzioni (CCC). Visit www.herrenknecht.com and www.metrocspa.it
All the four EPB TBMs are identical. The first TBM (machine S-409 named "Shira") is working since 24th June, 2008 on the even track, i.e. the left tunnel from the Giardinetti station box towards the TBM reception shaft in San Felice da Cantalice Square in the city centre (section of about 4,000 metres). The first machine has already built some 200 metres of tunnel. The second TBM (machine S-410 dubbed "Filippa" on the uneven track) will begin to dig the parallel tunnel from 8th September, 2008 (same length, approx. 4,000 m).
The third TBM (machine S-479 christened "Diana" on the uneven track) will commence on 10th March, 2009 from the Malatesta shaft towards the TBM receiving pit in San Felice da Cantalice Square (approx. 2,800 metres of tunnel). The Malatesta shaft is located halfway between the Malatesta and Teano stations. On 29th August, this third TBM was tested in factory and will be assembled in November in the Malatesta launch box to start excavation towards Centocelle. The testing of the machine took place at the CMA/Herrenknecht facilities in Bassano del Grappa. The fourth and last TBM ordered to build Line C from Giardinetti to San Giovanni is TBM S-480 (still to be christened and to be used on the even track) will be tested at the end of October and will commence its job on 9th May, 2009 to dig the parallel tunnel from the same lauch shaft up to the same reception shaft (a section of about 2,800 metres).
Later on, two of the four TBMs will be re-used from the Malatesta shaft to San Giovanni (a section of about 2,700 metres).
The four TBMs for Line C are EPB shields featuring a 6.69 m-diameter cutting wheel dressed with steel tools and disc cutters to dig through silty sand, gravel and clayey silt. The cutterhead power equals 1,600 kW. The total thrust is 50,558 kN and the cutterhead torque is 9,000 kNm. Each TBM weighs 750 tonnes in all and is 100 m long, included the back-up (the trailing structure which houses the pilot cabin, the hydraulic, electrical and ventilation equipment and the conveyor belt that feed the fragmented rock into muck carts).
The TBM advances at about 8-12 metres per day with peaks of 20 metres and works 24 hours seven days per week. Every TBM shift includes nearly 15 people underground and 10 people overland.
TBMs are complex and use state-of-the-art technology, they are totally automatic and driven by a computer. A machine operator sitting in a cabin will control all the machine's functions and that it will not damage the foundations of local buildings. At the corners of the surrounding buildings, instrumentation will actually be installed to monitor and detect in real time the possible subsidence (even when imperceptible to man).
There will always be a ventilation, drainage or emergency shaft halfway between a station and the subsequent one. In case of two stations being more than 1 km to one another, it may be necessary to build an additional emergency-ventilation-safety shaft (for rescue of users).
Mucking-out
The ventilation ducting, 1,400 mm in diameter, is supplied by G&G Partners of Brescia. The fans are supplied by Zitron. The soil extracted from the face by the cutting wheel follows the following route: chamber behind the cutting wheel + conveyor belt + five muck cars (train) + dump area outside + vertical conveyor belt supplied by Continental Conveyor + horizontal conveyor supplied by CO.IM.IND. (Costruzioni Impianti Industriali) of Pomezia. The only two locomotives (two for each train) have been supplied by GIA Industri (Anbel being their Italian agent), while the cars are from Valente. Visit www.zitron.com, www.continental-conveyor.co.uk, www.gia.se, www.anbel.com and www.valente.it
Six TBMs to Expand Rome's Metro System
Herrenknecht's EPB TBM S-410 dubbed "Filippa"

Support and lining
Inside the shield tail, a mechanical erector installs the final lining made up of curved precast concrete segments which, assembled together, shape the support rings of the tunnel. Every ring has seven segments (seven and a key). The segments are surrounded by a rubber gasket for waterproofing, manufactured by FIP of Padova. FIP supplies besides the secondary PVC and nylon fasteners and accessories to shape the seven-element lining rings and connect them together. Visit www.fip-group.it
The segment production plant is partly existing. The segments are precast in Vianini Industria's facility in Aprilia. The plant has been completely streamlined and redeveloped to produce segments for Line C. The moulds, all new, have been designed by Metro C SpA and supplied by Euroform. Visit www.euroformsrl.it
The annular space grouting equipment has been supplied by Tecniwell (Piacenza) and the cementitious grout admixtures by Mapei. Even the grout has been studied by Metro C engineers, Mapei and the Turin polytechnic school. Visit www.tecniwell.com, www.mapei.it and www.polito.it/ricerca/dipartimenti/index.en.html
Benefits of Line C
Line C will serve 39 new stations along 34 km of track from Grottarossa in the north of the city to Pantano to the southeast, including nine stops (Grottarossa-Vignola) not in the original plans: Grottarossa, Tomba di Nerone, Villa San Pietro, Parco di Veio, Giochi Delfici, Giochi Istmici, Farnesina, Auditorium, Vignola, Clodio/Mazzini, Ottaviano (connection to Line A), Risorgimento, San Pietro, Chiesa Nuova, Argentina, Venezia, Colosseo (connection to Line B), Amba Aradam, San Giovanni (connection to Line A), Lodi, Pigneto (connection to regional train line FR1 Fiumicino airport-Fara Sabina), Malatesta, Teano, Gardenie, Mirti, Parco di Centocelle, Alessandrino, Torre Spaccata, Figlioli, Giardinetti, Torre Angela, Torre Gaia, Grotte Celoni, Fontana Candida, Borghesiana, Bolognetta, Finocchio, Graniti (central control office), Pantano. Journey time from one end of the line to the other will be around 60 minutes. Parking facilities will be provided at Grottarossa, Villa San Pietro, Parco di Veio, Farnesina, Clodio/Mazzini, Teano, Alessandrino, Torre Angela and Pantano stations.
Passengers will be separated from tracks by sliding doors that open only when a train is present. Thirty automatic driverless trains will be operated from a central control office at Graniti and will carry up to 600,000 passengers daily. The technologically advanced Line C will be the first major public heavy rail transport infrastructure in Italy to be remotely guided and controlled by a fully automated system.
A new underground museum near Colosseo station will exhibit the archaeological finds of the Line C teams that have been removed. Click here. Visit www.archeorm.arti.beniculturali.it
The total cost of Line C will be around EUR4.2 billion, of which the Italian government will provide 70%, the city of Rome 18% and the region of Lazio 12% (although financing for the Grottarossa-Clodio/Mazzini section has yet to be finalised).
Construction of Line C is divided in several sections built according to different time frames. At the moment, work is ongoing at 26 sites along the route between San Giovanni and Monte Compatri/Pantano, 10 of which between the Pantano station and Giardinetti, a section of the Rome-Pantano regional line closed to commercial traffic since 7th July. From the line terminus at Monte Compatri-Pantano to the tunnel mouth in Torrenova, the line will remain at grade and provide service, after enhancement, on the same alignment as the present Rome (Laziali)-Pantano line. The first section of Line C Monte Compatri/Pantano-Centocelle is expected to open by the end of 2011, the extension to Lodi in the second half of 2012, while the opening of the entire line from Clodio/Mazzini to Monte Compatri/Pantano is scheduled by 2015. Click it/14. Visit www.romametropolitane.it

Six TBMs to Expand Rome's Metro System

Line B1
Mayor of Rome Gianni Alemanno launched on 21st May, 2008 in Conca d'Oro Square the first of two tunnel boring machines that will dig and line the first bore of a twin tunnel of Line B1 to Bologna Square. The project forms part of a EUR42 million job subcontracted to SELI by a joint venture of Salini and Maire Engineering. SELI's assignment includes the digging and lining of two tunnels stretching for 5,638 metres altogether and driven by two earth pressure balance (EPB) shields supplied by Herrenknecht (machines S-387 and S-388). The bored diameter is 6,770 mm. The EPB technology uses suction to hold on to the loose soil created while digging the tunnel, untill the concrete lining is made along the walls. The machines feature a cutterhead power of 1,600 kW, a cutterhead torque of 6,967 kNm and a total thrust of 50,000 kN. Visit www.selitunnel.com
Geology is silty sand, silty clay and clayey to sandy silt. Tunnelling takes place at a depth of 25-30 metres. The back-up system behind the TBM has been designed and manufactured by SELI in the company's plant in Aprilia near Rome for certain parts and by other European subcontractors for others. Each TBM and its trailing gear is 100 m long in all and excavates and installs the 35 cm-thick precast concrete segmental rings. The tunnel's inner diameter is 5.80 m.
The second TBM will build from September the second, parallel Bologna-Conca d'Oro tunnel, also from Conca d'Oro. The two TBMs will work under a pressure of 5 bar able to wistand the ground pressure and hydrostatic pressure. The machines will achieve an average advance rate of 10 m/day. The soil will be transported to the Conca d'Oro entry shaft by conveyor belt.
Construction of Line B1 involves an area as wide as the city of Bologna. The line will carry 24,000 people per hour in each direction. Excavation started five months ahead of schedule and it is hoped that the line, with its twin tunnel between Bologna Square and Conca d'Oro Square, will start operating in spring 2011. There will be two intermediate stops at Annibaliano and Libia/Gondar. Click it/31. Visit www.romametropolitane.it 36/08.