Amirkabir Journal of Civil Engineering

Amirkabir Journal of Civil Engineering

Effects of Urban Tunnel Excavation in Tehran in Response to Existing Static and Dynamic Structures in Terms of Soil and Structure Interaction

Document Type : Research Article

Authors
Mehdi faraj mohammadieh 1
Farhad Behnamfar 2
seyed jahed mohammadi 3
1 Instructor of Razi Technical School of Ardabil
2 Isfahan University of Technology
3 PhD student of Structural Engineering, Zanjan University, Razi University of Technology, Ardabil
10.22060/ceej.2020.17201.6493
Abstract
Excavation of tunnels can cause the earth to move, which is significant in the static and dynamic response of structures. In this study, the effect of tunnel excavation in Tehran city on the dynamic and static response of structures in three sections has been investigated. In the first part, PLAXIS software calculates the following two-step session before and after excavating. The second part of PLAXIS also performs dynamic analysis for both stages and the following acceleration response is calculated. The purpose of the second part is to investigate the impact of excavating on acceleration response and its use in SAP 2000 software as input for structural analysis. In the third part, the structure is modeled in SAP 2000 software and the results of the first part of the displacements of footing are applied and by using accelerating response, the structure`s nonlinear dynamic analysis is performed in two stages (PLAXIS output). The results of the analysis showed that the tunnel excavation has increased the subsidence of the foundation subsurface and the highest subsidence is in the 6th model (operation stage), which is 1.2 times the average of the previous one. The excavation has increased and the impact of the supporting structures during the execution phase compared to the operation stage where the concrete side walls are executed has been effective in reducing the subsidence by 4% and maximizing the acceleration below 1.5 times and also in the structures the displacement increased by 1.25 times compared to the pre-excavation phase response.
Keywords
Urban tunnel
Excavation
Supporting structures
Dynamic analysis
Subsidence
Subjects
  1. Castaldo, P., et al. (2014). "Structural safety of existing buildings near deep excavations." International Journal of Structural Engineering 5(2): 163-187.
  2. Long, M. (2001). "Database for retaining wall and ground movements due to deep excavations." Journal of Geotechnical and Geoenvironmental Engineering 127(3): 203-224.
  3. Moormann, C. (2004). "Analysis of wall and ground movements due to deep excavations in soft soil based on a new worldwide database." Soils and foundations 44(1): 87-98.
  4. Doğangün, A., et al. (2007). "A study on seismic behavior of minarets considering soil-structure interaction."
  5. Wang, J. (1993). "Seismic design of tunnels: a state-of-the-art approach, monograph, monograph 7." Parsons, Brinckerhoff, Quade and Douglas Inc, New York.
  6. Hashash, Y. M., et al. (2001). "Seismic design and analysis of underground structures." Tunneling and underground space technology 16(4): 247-293.
  7. Cottonaro, R. D., et al. (2019). "Retrofitting of existing tunnels with concrete lining: a preliminary experimental investigation." Retrofitting of existing tunnels with concrete lining: a preliminary experimental investigation: 95-104.
  8. Lunardi, G., et al. (2019). "Refurbish and static reinforcement of tunnels: innovative construction methods and materials." Refurbish and static reinforcement of tunnels: innovative construction methods and materials.: 12-20.
  9. Castaldo, P. and M. De Iuliis (2014). "Effects of deep excavation on seismic vulnerability of existing reinforced concrete framed structures." Soil Dynamics and Earthquake Engineering 64: 102-112.
  10. Doğangün, A., et al. (2007). "A study on seismic behavior of minarets considering soil-structure interaction."
  11. Castaldo, P., et al. (2013). "Probabilistic analysis of excavation-induced damages to existing structures." Computers and Geotechnics 53: 17-30.
  12. Fatah El Zadeh, Mechanical and Dynamic Modeling of Earth Structures in PLAXIS, Publisher by Noavar (1394). (In Persian)
  13. Gohari, Vafaiepor, Finite Element Code for soil and Rock Analyses PLAXIS, Publisher by Forozesh (1392) (In Persian).
  14. Pak Neiat, Analyese dynamic Earthquake, Publisher by Motafakeran (1392). (In Persian)
  15. Steven L. KRAMER, Geotechnical seismic, Mir Hoseini. Research Earthquake Esfahan (1385). (In Persian)
Amirkabir Journal of Civil Engineering
Volume 53, Issue 5
August 2021
Pages 1889-1916