Assessing the results of work on strengthening the soils of the foundation of lock № 5 of the Volga-Don shipping canal and proposals for stabilizing the chamber position

The results of work to strengthen the soil foundation of the chamber of lock № 5 of the Volga-Don Shipping Canal, carried out in 2016–2017, are analyzed. The need to carry out work to strengthen the soil was caused by an increase in the intensity of sedimentation of the central sections of the lock chamber, which began in 2005. To stabilize the chamber position, the technology of two-component jet grouting is implemented. This technology assumes the formation of several longitudinal soil-cement walls in the soils of the lock chamber base, which would transfer the load from the weight of the chamber to the harder clay soils of the water-resistant layer. However, as a result of the work performed, the precipitation intensity has increased. Engineering-geological, hydrological and geophysical studies conducted in 2018–2020 recorded the absence of formed soil-cement elements in the soils of the chamber base. An analysis of the soil samples characteristics taken from the chamber base has showed that a layer of soils of 10–12 m thickness is composed of loess rocks, below which water-resistant clayey rocks lie. Initially, there were several confined and non-confined aquifers in the soils of the lock base, and the creation of a hydroelectric complex and the formation of a level difference between the upper and lower pools led to the formation of a filtration flow with a significant pressure gradient at the base of the chamber. An analysis of the properties and structure of loess soils has showed their predisposition to subsidence, transition to a floating state and liquefaction with an increase in water content. Under the conditions of weak water-saturated loess soils, the supply of a cement mixture into them under significant pressure did not lead to the formation of soil-cement elements. Thus, in accordance with the current regulatory documents, the technical condition of the gateway is defined as pre-emergency, and the security level is defined as unsatisfactory. Methods for reducing the intensity of the chamber sedimentation such as cutting through the loess layer with piles, physical and chemical strengthening of soils and water protection of the massif at the base of the chamber are considered and evaluated.

1. Tekhnicheskii otchet o stroitel’stve Volgo-Donskogo sudokhodnogo kanala imeni V. I. Lenina, Tsimlyanskogo gidrouzla i orositel’nykh sooruzhenii 1949–1952 v pyati tomakh. Vol. 1. M: Gosenergoizdat, 1957.

2. Koblev, I. I., V. A. Krivoshei, O. Yu. Shakhmardanov, and V. Ya. Shestakov. Volgo-Donskoi sudokhodnyi kanal. 2nd edition. Volgograd: Izdatel’, 2012.

3. Instruktsiya po nablyudeniyam i issledovaniyam na sudokhodnykh gidrotekhnicheskikh sooruzheniyakh. Vol. 1. M.: Transport, 1981.

4. Provedenie issledovatel’skikh rabot, poverochno-teoreticheskikh raschetov prochnosti i ustoichivosti konstruktsii shlyuzov № 5, 10, 11, 12, 13, 15, gruntovoi damby № 74, napornogo truboprovoda № 34 nasosnoi stantsii № 32 Volgo-Donskogo sudokhodnogo kanala s tsel’yu ustanovleniya fakticheskogo tekhnicheskogo sostoyaniya, zapasov prochnosti i nesushchei sposobnosti sooruzhenii i oborudovaniya, razrabotka kriteriev bezopasnosti. Scientific report. SPb.: FGOU VPO SPGUVK, 2008.

5. Razrabotka i realizatsiya kompleksnogo proekta rekonstruktsii Volgo-Donskogo sudokhodnogo kanala. I etap. Tretii puskovoi kompleks. Rekonstruktsiya gidrouzla № 5, pervaya ochered’. Volgograd: OOO «SSM», 2013.

6. Metodicheskie rekomendatsii po kontrolyu tekhnicheskogo sostoyaniya i otsenke bezopasnosti sudokhodnykh gidrotekhnicheskikh sooruzhenii. M., 2011.

7. Provedenie nablyudenii i spetsial’nykh issledovanii za shlyuzom № 5 posle vypolnennykh rabot po ukrepleniyu gruntov osnovaniya dlya razrabotki rekomendatsii po provedeniyu rabot po ukrepleniyu gruntov osnovaniya shlyuza № 6 Volgo-Donskogo sudokhodnogo kanala. SPb.: FGBOU VO GUMRF im. adm. S. O. Makarova, 2020.

8. Mustakimov, V. R. Iskusstvennye osnovaniya zdanii i sooruzhenii na prosadochnykh gruntakh: uchebnoe posobie dlya vuzov. M.: Izdatel’stvo Yurait, 2023.

9. Sviderskikh, A. V., and I. V. Noskov. “Analysis of characteristics changes in the loess soils depending on porosity.” The Eurasian Scientific Journal 11.2 (2019): 74.

10. Ryashchenko, T. G. Regional’noe gruntovedenie (Vostochnaya Sibir’). Irkutsk: IZK SO RAN, 2010.

11. Shvetsov, A. Ya. Lessy Altaya. Barnaul: Izd-vo «Novyi format», 2021.

12. Vyskrebentsev, V. S. “Structural behavior of loess subsiding soils under permanent and dynamic load.” Bulletin of Belgorod state technological university named after. V. G. Shukhov 3 (2016): 38–42. DOI: 10.12737/issn.2071-7318.

13. Trofimov, V. T., V. A. Korolev, E. A. Voznesenskii, G. A. Golodkovskaya, Yu. K. Vasil’chuk, and R. S. Ziangirov. Gruntovedenie. 6th ed. M.: Izd-vo MGU, 2005.

14. Morgunov, K. P. Gidravlika gidrotekhnicheskikh sooruzhenii. SPb.: Lan’, 2022.

15. Morgunov, K. P., and M. A. Kolosov. “Soil Liquefaction Problems in the Foundations Hydraulic Structures.” Science and Technique 21.3 (2022): 201–210. DOI: 10.21122/2227-1031-2022-21-3-201-210.

16. Morgunov, Konstantin P. “Influence of the soils properties in the base of shipping locks on their performance.” Vestnik Gosudarstvennogo universiteta morskogo i rechnogo flota imeni admirala S. O. Makarova 13.5 (2021): 670–684. DOI: 10.21821/2309-5180-2021-13-5-670-684.

17. Igosheva, L.A., and A. S. Grishina. “Review of the basic methods of the ground improvement.” Construction and Geotechnics 7.2 (2016): 5–21. DOI: 10.15593/2224-9826/2016.2.01.

18. P’yankov, S. A. Svainye fundamenty. Ul’yanovsk: UlGTU, 2007.

19. Zheleznyakov, V. A., A. P. Aleksandrov, and A. S. Kulikov. “Increasing the bearing capacity of a bored pile by silicatization.” Inženernyj vestnik Dona 11(71) (2020): 321–328.

20. Kondrashin, K. G., V. N. Pilipenko, and E. M. Golubnicheva. “Vozmozhnost’ termicheskogo ukrepleniya gruntov.” Inzhenerno-stroitel’nyi vestnik Prikaspiya: nauchno-tekhnicheskii zhurnal 2(36) (2021): 20–25.

21. Yurdanov, A. P. Termicheskoe uprochnenie gruntov v stroitel’stve. M.: Stroiizdat, 1990.