Scientific-Research Planning and Surveying Institute «Lenmetrogiprotrans» (St. Petersburg, Russia):

Maslak V. A., Chief Executive Officer, Candidate of Engineering Sciences, e-mail: Maslak@lenmetro.ru
Bezrodny K. P., Deputy Chief Executive Officer, Doctor of Engineering Sciences
Lebedev M. O., Head of Laboratory

National Mineral Resources University (St. Petersburg, Russia):

Gendler S. G., Professor, Doctor of Engineering Sciences

This article shows the following urgent problems:
- decrease in influence of technological processes, accompanying underground construction on a terrestrial surface and preservation of buildings and connected constructions;
- ensuring standard parameters of noise and vibration in operation time.
Stability of a social situation depends on the successful solution of these problems in place of residence of people and maintenance of aesthetic value of the megalopolis districts with unique cultural and historical significance. The most advanced directions of solution of these problems are application of construction technology of underground roadway with low areal deformation of terrestrial surface, which provide minimization of impact of building and operation processes on environment. The underground construction in St. Petersburg was carried out in very difficult engineering-geological conditions, in the flooded, extremely unstable rocks. Experience of underground building testifies that the greatest influence on earth areal deformation, using the brine-freezing based traditional technologies, takes place at construction of escalator tunnels. This article describes the innovative technologies of underground construction in St. Petersburg, which allow to reduce areal deformation of terrestrial surface and to prevent the process of buildings' destruction. One of such technologies is the combined technology, conjoining jet cementation, and brine freezing of soil. Efficiency of use of offered combined technology was confirmed with comparison of the date of experimental investigations of areal deformation of terrestrial surface to technology of construction by brine freezing method. Other direction of decrease of areal deformation of earth at construction of escalator tunnels is connected with application of tunnel boring mechanized machine. During the construction, the tunnel boring mechanized machine use the escalator tunnels, allowed to reduce the areal earth deformation considerably from 95 mm at “Obvodnoy Kanal” station to 46 mm at “Admiralteyskaya” station and 25 mm at “Spasskaya”station. Technological development of underground building by tunnel boring mechanized machine allows to construct the double-track tunnels with non-standard concrete lining, which simultaneously permits to reduce vibration impact of trains on buildings and constructions, located on a surface to guideline value.

1. Bezrodnyy K. P., Salan A. I., Maslak V. A., Lebedev M. O., Starkov A. Yu., Morozov A. V., Ukhanov A. V. Transport Rossiyskiy Federatsii — Transport of Russian Federation, 2010, No.  3(28), pp. 38—41.
2. Bezrodnyy K. P., Lebedev M. O., Ukhanov A. V. Izvestiya Tulskogo Gosudarstvennogo Universiteta — Proceedings of Tula State University, 2009, No. 4, pp. 25—30.
3. Giginyak E. I. Metro i Tonneli — Metro and Tunnels, 2009, No. 5, pp. 4—5.
4. Starkov A. Yu., Laptev N. A. Metro i Tonneli — Metro and Tunnels, 2010, No. 1, pp. 22—23.