Installation of the tunnel protective shield for construction of the highway tunnel at km 677 of Moscow – St. Petersburg M-11 Highway is close to completion. The tunnel under the operating Warsaw Direction railways is one of the key structures of Saint Petersburg section of M-11. The construction works are carried out without interruption of the railway traffic.
Two Tunnel Boring Machines (TBM) ensure rock tunneling construction with arrangement of the protective shield. Tunnel invert, walls and crown out of cast-in-situ reinforced concrete will be constructed stage-by-stage.
The protective shield inside embankment under Warsaw Direction railway tracks ensures railway traffic during the whole period of the tunnel construction works. Protective shield is made of tubular steel structures. Fifty metal pipes of different length (from 52.8 m to 66 m each) are to be embedded into the embankment by the TBMs. The embedding process is fully automatic: controlled by an operator, equipped with a jacking station, a laser guided system, a system of feeding, benefication and refining of concrete.
As of today, 29 horizontal and 18 vertical pipes have been embedded (47 out of 50 pipes). The railway embankment is under constant geodetic monitoring of deformations in order to ensure safe railway traffic. Upon completion of the protective shield installation, main tunneling works will start together with reinforcing of tunnel walls with cast-in-situ reinforced concrete. Tunnel excavation and lining out of reinforced concrete will be carried out in the 2nd quarter of 2017.
Tunnel length – 74.9 m
Tunnel height – 5.52 m (with 5.2 m clearance)
Number of traffic lanes – 6 (3 lanes for each direction)
Tunnel construction commencement – April 2016
Tunnel construction completion – December 2017
Take note that the construction of Sections 7 & 8 of Moscow – St. Petersburg Highway has been started in June 2015. 137.6 km section of M-11 starts from the Ring Road of Saint Petersburg then passing through the territories of Moskovsky and Pushkinsky Districts of Saint Petersburg, through Tosnensky District of Leningrad Region, as well as through Novgorodsky and Chudovsky Districts of Novgorod Region. Excavation works, embankment filling and base course filling, construction works on engineering structures are in progress. About 2000 people and over 600 units of machinery are engaged in construction works at the Facility. All the works meet the construction schedule. Completion of them is planned for the middle of 2018.