Underground Contruction

Extension of the Third metro line of Sofia metropolitan and construction of MS 6 "Teatralna" and MS 8 "Orlov most"

The project is funded by: OP “Transport and Transport Infrastructure” 2014-2020
Budget: 75 582 000 BGN
Start date: 05 Jan 2016
End date: 15 Apr 2020
Employer: Metropoliten JSC
Contractor: Consortium „METRO CONSTRUCTION”

The official opening ceremony of Sofia’s third metro line took place on 26 August, 2020. The project first stage having a length of 8 km and covering 8 metro stations was put into operation on the same day. Metro stations 5 “Hadzhi Dimitar”, 6 “Teatralna” and 8 “Orlov most”have been designed by the team of Arch. Konstantin Kosev and constructed by engineers and builders of the team of “Trace Group”. Project manager has been Dipl. Eng. Petar Kostov. The three mentioned metro stations were implemented by Trace and partner companies in consortiums. The other two metro stations that have been executed by Trace within Sofia’s third metro line – MS 17 and MS “Gorna Banya” are currently in a test mode.

MS 5 and MS 6 have been difficult to implement due to diverse geological conditions through which the tunnel section passes, high groundwater and proximity of the stations to Perlovska River correction (the northern entrance of MS 5 passes under the river and exits on the sidewalk of “Vladimir Vazov” Blvd.). In an interview, Dipl. Eng. Boyan Delchev, Trace CEO said: "The way in which the transition between metro stations 5 and 6, under an existing railway line, at an extremely little height from the top of the tunnel to the rail level, sand and water soils, is an example for the fact that Bulgarian engineers know what to do and how to do it. The tunnel boring machine reached MS 5, which required a full meet of deadlines”. MS 8 Orlov Most is the deepest metro station in Sofia.

* * * 

The present contract includes the design and construction of the specified position No. 3. The construction of two underground metro stations have been provided (MS 6 and MS 8) and tunnel section after MS 6, which have a length of 191,45 m. MS 6 was constructed by open method and MS 8 and the tunnel section after MS 6 - by the new Austrian tunnel method. The length of the metro section is 1,611.05 m. The contract also required the complete equipment of the two metro stations and the tunnel section.

Partners in the Consortium "METRO CONSTRUCTION" are "Trace Group Hold" PLC, "Evro Alliance Tunnels" AD and "Injproekt" OOD. Duration of the project implementation was 45 months.

Video on laying concrete between MS 5 and MS 6 you can see here.

Tunnel Boring Machine video is available here.

Video on "Orlov most" Metro station is available here.

Video on "Teatralna" Metro station is available here