Numerical analysis of reducing tunneling effect on viaduct piles foundation by jet grouted wall

Kamel Asker¹, Mohmed Tarek Fouad², Mohamed Bahr², Ahmed El-Attar¹

¹Higher Technological Institute, Cairo, PO Box 228, Egypt

²Al-Azhar University, Cairo, 11751, Egypt

Min. miner. depos. 2021, 15(1):75-86

https://doi.org/10.33271/mining15.01.075

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ABSTRACT

Purpose. The target of this study is divided into two parts. The first part is concerned with capability of numerical model to simulate the tunneling process. The second part is related to studying the interaction mechanism between the tunnel, protection technique, and soil. This study themes are investigated by analyzing different protection technique configuration, considering different stiffness of the grouted wall, and applying different interface coefficient between the wall and the soil.

Methods. The method used in this study to check the accuracy of the proposed numerical model is 4-D ABAQUS program. The typical excavation of a tunnel is simulated step by step with an assumed rate of tunnel advancement (0.5 to 1.5 m/hr). The soil material utilized in this model is elastic perfectly plastic (the Mohr-Сoulomb criterion), while elastic material is modeled as solid element (S4R) adopted for lining, grouting, filling gaps, shielding, constructing piles, and jet grouted wall.

Findings. Results showed that the closer jet grouting to the tunnel with embedded length of 1.5 times tunnel diameter, the better effect on reducing the lateral deformation and bending moment generated on piles. Otherwise, increasing wall thickness more than double grouted column diameter would not affect its shielding efficiency. Furthermore, either increasing or decreasing friction coefficient even if rough between the grouted wall and soil had no effect on the pile behavior. Additionally, applying Mohr-Coulomb criteria for grouted wall with high stiffness allowed realistic response of the pile group.

Originality.Capability of the proposed model is verified by back analysis of Changsha Subway Line 1 project, where the shield tunnel would be constructed near existing pile groups of L off-ramp of the Xinzhong Road viaduct.

Practical implications. Increasing grouted wall configuration is more effective than mechanical properties or its interface coefficient with surrounded soil in mitigating tunneling effect on nearby piles.

Keywords: tunneling, jet grouting, gield measurements, ABAQUS, Changsha Subway Line 1

REFERENCES

Xiang, Y. Jiang, Z., & He, H. (2008). Assessment and control of metro-construction induced settlement of a pile-supported urban overpass. Tunneling and Underground Space Technology, 23(3), 300-307.https://doi.org/10.1016/j.tust.2007.06.008
Bilotta, E., & Russo, G. (2011). Use of a line of piles to prevent damages induced by tunnel excavation. Journal of Geotechnical and Geoenvironmental Engineering, 137(3). https://doi.org/10.1061/(ASCE)GT.1943-5606.0000426
Ng, C.W., Lu, H., & Peng, S.Y. (2013). Three-dimensional centrifuge modelling of the effects of twin tunneling on an existing pile. Tunneling and Underground Space Technology, (35), 189-199. https://doi.org/10.1016/j.tust.2012.07.008
Zou, W.H., & Xu, M. (2013). 3D numerical analysis of mitigation effect of separation pile and diaphragm wall considering small strain stiffness of soils. Chinese Journal of Geotechnical Engineering, (1), 203-209.
Bai, Y., Yang, Z., & Jiang, Z. (2014). Key protection techniques adopted and analysis of influence on adjacent buildings due to the Bund Tunnel construction. Tunneling and Underground Space Technology, (41), 24-34.https://doi.org/10.1016/j.tust.2013.11.005
Nematollahi, M., & Dias, D. (2019). Three-dimensional numerical simulation of pile-twin tunnels interaction – Case of the Shiraz subway line. Tunneling and Underground Space Technology, (86), 75-88.https://doi.org/10.1016/j.tust.2018.12.002
Fu, J., Yang, J., Zhu, S., & Shi, Y. (2016). Performance of jet-grouted partition walls in mitigating the effects of shield-tunnel construction on adjacent piled structures. Journal of Performance of Constructed Facilities, 31(2), 04016096.https://doi.org/10.1061/(ASCE)CF.1943-5509.0000961
EL-Attar, A.N. (2018). Reducing the tunneling effect on adjacent pile foundations. Engineering Challenges for Sustainable Underground Use, 160-172.
Li, P., Lu, Y., Lai, J., Liu, H., & Wang, K (2020). A Comparative study of protective schemes for shield tunneling adjacent to pile groups. Advances in Civil Engineering, (2020), 6964314. https://doi.org/10.1155/2020/6964314
Pawtucket, R.I. (2016). ABAQUS user’s manual. ABAQUS Inc. Version 6.16.
Moller, S. (2006). Tunneling induced settlements and structure forces in linings. Ph.D. Thesis. Stuttgart, Germany. Stuttgart University.
ACI-Building-Code. (2011). ACI 318-11 Building code requirements for structural concrete and commentary. Farmington Hills, United States: American Concrete Institute.
Vermeer, P.A., & Bonnier, P.G. (1991). Pile settlements due to tunneling. Proceedings of the 10th European Conference on Soil Mechanics and Foundation Engineering, 869-872.
Technical specification for building pile foundation, geotechnical mechanics. (2008). Beijing, China: Ministry of Housing and Urban-Rural Construction of the People’s Republic of China.
Tan, D.Y., & Clough, G.W. (1980). Ground control for shallow tunnels by soil grouting. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 18(2), 36-1058. https://doi.org/10.1016/0148-9062(81)90940-2
Bell, F.G. (1993). Engineering treatment of soils. London, United Kingdom: E & FN SPON. https://doi.org/10.4324/9780203474181
Cho, G., Kim, J., & Song, K. (2008). Analysis of pre-reinforced zone in tunnel considering the time-dependent performance. Geotechnical Aspects of Underground Construction in Soft Ground. https://doi.org/10.1201/9780203879986.ch99
Fantera, L., Rampello, S., & Masini, L. (2016). A mitigation technique to reduce ground settlements induced by tunnelling using diaphragm walls. Procedia Engineering, (158), 254-259. https://doi.org/10.1016/j.proeng.2016.08.438