Evaluation of Seepage Force and Overall Stability Factor Along Proposed Baghdad Metro Tunnel Across Tigris River
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Abstract
Baghdad Metro is a vital project to fulfill the rapidly increased traffic volume requirements. The proposed metro will connect both sides of Baghdad City, passing under the Tigris River. This study is employed finite elements software (PLAXIS 3D) to evaluate the seepage force developed around the sub-river segment during different construction stages and for other water levels of Tigris. The study found that when the water level changes from maximum to minimum, the developed seepage force decreases by (8 to 13%) and (22 to 27%) respectively. The seepage forces were found to be maximum during the excavation stage. The concrete lining process led to a noticeable reduction in seepage forces at all locations. The study also implemented the strength reduction theory to assess the overall stability of the tunnel. The study shows that the overall stability factor was minimum during the concrete lining process. As the water level decreased, the overall stability factor increased by (5% - 8%).
Article received: 20/7/2022
Article accepted: 7/9/2022
Article published: 1/2/2023
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Al-Khailany, D. K., Saleh, M. M., and Daraei, A., 2022. Evaluating the Moisture Content Variation on Critical Strain of Geo-materials: A Case Study, Journal of Engineering, 28(6), pp.27-38.
Al-Taee, M. H. A., 2018. Assessment of GW pressure effects around the Tunnel - Baghdad Metro, Ph.D. Thesis, University of Technology – Iraq.
Asaad, B. I., and Abed, B. S., 2020. Flow Characteristics Of Tigris River Within Baghdad City
During Drought, Journal of Engineering, 26(3),pp. 77-92.
Bouvard, M., and Pinto, N., 1969. Amenagement Capivari-Cachoeira: Etude Dupuits en Charge, La Houille Blanche, No. 7, pp.747-760.
Das B.M., Sobhan K., 2014. Principle of geotechnical engineering, Pearson.
Fernández, G., and Alvarez Jr, T. A., 1994. Seepage-induced effective stresses and water pressures around pressure tunnels, Journal of Geotechnical Engineering, 120(1), pp.108-128.
Hamid, A. A., and Husain, H. A., 2021. Evaluation of Water seepage Along Proposed Baghdad Metro Tunnel Across Tigris River, Al-Nahrain Journal for Engineering Sciences, 24(2), pp.149-158.
Isacc S. Alakaam, 2019. A study of some morphological characteristics of the Tigris River in the City of Baghdad, University of Baghdad – College of Science (In Arabic).
Kai Su, Yafeng Zhou, Hegao Wu, Changzheng Shi, and Li Zhou, 2017. An Analytical Method for Groundwater Inflow into a Drained Circular Tunnel, Groundwater Summit, 55 (5), pp.712-721.
Zhang L., D. Zhao, J. Wu, W. Yang, W. Wang, and D. Xi, 2020. Prediction of water inflow in Tsingtao subsea tunnel based on the superposition principle, Tunnelling and Underground Space Technology, 97(103243), pp.1-12.
Lü, X., Zhou, Y., Huang, M., and Zeng, S., 2018. Experimental study of the face stability of shield tunnel in sands under seepage conditions, Tunnelling and Underground Space Technology, 74, pp.195-205.
NCCLR: National Center for Construction Labs and Researches, Baghdad, Iraq.
Park, K.-H., Tontavanich, B., and Lee, J.-G., 2008. A simple procedure for the ground response curve of a circular tunnel in elastic-strain softening rock masses, Tunnelling and Underground Space Technology, 23, pp.151–159.
PLAXIS 3D Manual, 2020. Delft University of Technology & bv PLAXIS, Netherland.
PLAXIS 3D Software verification manual, 2013. Delft University of Technology & PLAXIS bv, Netherland.
Schleiss, A. J., 1986. Design of previous pressure tunnels, Water Power and Dam Construction, 38(5), pp.21-26.
Wang, F., Zhang, C., Zhou, H., Liu, N., Zhang, Y., Azhar, M. U., and Dai, F., 2017. The long-term safety of a deeply buried soft rock tunnel lining under inside-to-outside seepage conditions, Tunnelling and Underground Space Technology, 67, pp.132-146.
Yang, X. L., and Huang, F., 2009. Stability analysis of shallow tunnels subjected to seepage with strength reduction theory, Journal of the Central South University of Technology, 16(6), pp.1001-1005.
Yoo, C., and Kim, S. B., 2008. Three-Dimensional Numerical Investigation of Multifaced Tunnelling in Water-Bearing Soft Ground, Canadian Geotechnical Journal, 45, pp. 1467-1486.
Yoo, C., 2005. Interaction between Tunnelling and Ground Water-Numerical Investigation Using Three-Dimensional Stress-Pore Pressure Coupled Analysis, Journal of Geotechnical and Geoenvironmental Engineering, 131(2), pp. 240-250.
Yoo, C., Kim, S. B., Lee, Y. J., Kim, S. H., and Kim, H. T., 2007. Interaction between Tunnelling and Ground Water–Its Impact on Tunnel Behaviour and Ground Settlement, Underground Space–The 4th Dimension of Metropolises– Barták, Hrdina, Romancov and Zlámal (eds), pp. 939-944.
Yoo, C., Kim, S. B., Shin, H. C., and Baek, S. C., 2005. Effect of Tunnelling and Ground Water Interaction on Ground and Lining Responses, Underground Space Use: Analysis of the Past and Lessons for the Future – Erdem and Solak (eds), pp. 217-223