Stability analysis when tunnelling in soft soil condition in Hochiminh city

The rapid development in the economy and the urban population in cities in Vietnam in recent years leads to dramatic growth in traffic congestion, noise and air pollution, and environmental degradation. Urban underground infrastructure thus becomes an inevitable solution since the surface space becomes too expensive and restricted in spite of the high cost of tunnel construction. However, tunnelling in deltaic urban areas, in particular in the cases of Mekong Delta and Red River Delta areas, often faces to difficulties of soft soil conditions and the existence of important historical buildings on the surface. The first metro line constructed in Vietnam from Ben Thanh to Suoi Tien, which is located under crowded areas of Hochiminh city, was tunnelled in such conditions. This paper presents a back analysis for the stability of the tunnelling process in the project. The minimum support pressures is estimated by using the wedge model proposed by Jancsecz, S., & Steiner, W. (1994). Meanwhile, the maximum support pressure is estimated by the blow-out model proposed by Vu et al. (2016). Based on these results, the range of support pressures recommended for the Earth Pressure Balance Tunnel Boring Machine in the Hochiminh Metro Line No.1 project soft soil conditions is derived and compared to in situ support pressures obtained from the monitoring data in this tunnelling project. The study result shows a good agreement between the support pressures obtained from stability analysis models and the monitoring data from the construction site. Based on this back analysis, some recommendations are proposed with the purpose of successful construction in the next tunnelling projects in Hochiminh city.

How to Cite

Vu, N.Minh 2022. Stability analysis when tunnelling in soft soil condition in Hochiminh city (in Vietnamese). Journal of Mining and Earth Sciences. 63, 3a (Jul, 2022), 41-49. DOI:https://doi.org/10.46326/JMES.2022.63(3a).05.

References

Anagnostou, G. and Kovári, K. (1994). The face stability of slurry-shield-driven tunnels. Tunnelling and Underground Space Technology, 9(2):165-174.Balthaus, H. (1991). Tunnel face stability in slurry shield tunnelling. In Proceeding 12th International Conference on Soil Mechanics and Foundation Engineering, Rio de Janeiro, 13-18 August 1989 V2, P775-778, volume 28, page A391. Pergamon.Bezuijen, A. and Talmon, A. (2008). Processes around a TBM. In Proceedings of the 6th International Symposium on Geotechnical Aspects of Underground Construction in Soft Ground (IS-Shanghai 2008), pages 10-12.Broere, W. (2001). Tunnel Face Stability and NewCPT Applications. PhD thesis, Delft University of Technology.GIR (2015). Geotechnical interpretative report (Bored tunnel). HCMC-CP1b-TBMS-RPT-00073-C.Jancsecz, S. and Steiner,W. (1994). Face support for a large mix-shield in heterogeneous ground conditions. In the 7th International Symposium Tunnelling’94, held 5-7 July 1994, London.Kanayasu, S., Kubota, I., and Shikibu, N. (1995). Stability of face during shield tunneling-a survey of japanese shield tunneling. Underground Construction in Soft Ground,pages 337-343.TDRSM (2016) Technical design report forD6.79m shield machine. HCMC-CP1b-SPE-00001-D.Vu, M. N., Broere, W., and Bosch, J. W. (2015). The impact of shallow cover on stability when tunnelling in soft soils. Tunnelling and Underground Space Technology, 50:507-515.Vu, M. N., Broere, W., and Bosch, J. W. (2016). New blow-out models for shallow tunnelling in soft soils. Geotechnics for Sustainable Infrastructure Development - Geotec Hanoi 2016, Phung (edt). ISBN 978-604-82-0013-8.Vu, M. N., and Le, Q. H. (2020). Large soil-cement column applications in Vietnam. In Geotechnics for Sustainable Infrastructure Development (pp. 555-562). Springer, Singapore.

	Citations	842
	h-index	10
	i10-index	11

Abstracting & Indexing