Third underground line extension in Sofia from km 4+320 to km 4+950 with one underground station - MS 5 "Hadzhi Dimitar"

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 Orlov Most is the deepest metro station in Sofia.

* * *

Within the framework of the contract were carried out design, construction, technological equipment, complete execution and putting into operation of the section from km 4 + 320 to km 4 + 950 from the Third metro line with one metro station. In the section are included: Design, construction and putting into operation of one underground metro station (МS5) - constructive, architectural and additional works, railroad track, electrical part, including: Water supply and sewerage systems, HVAC, elevators and escalators installations, telecommunication /dispatching links, notification system - alarm system, clock system, fire alarm system, video control system, access control system, signaling system/, control and charging system for passengers, incl. technological equipment.

Main technical parameters:

- Track length, incl. the station - 630 m;

-  Including underground sections - 630 m, including the station;

- Number of underground metro stations - 1;

- Depth of installation: at the undergraund station - 12,0 m .; of the tunnel section - 14,0 m;

- Distance between stations - 800 m .;

- Maximum slope - 0.596%.

Laying a concrete on railway track between MS 5 and MS 6 you may see here.

Video on MS 5 - Hadzhi Dimitar is available here.