Simulation techniques and 3D modeling of TBM tunneling in soft and shallow grounds: A case study of Tehran metro line 6

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Mostafa Tarafrava
  • Arif Khan
  • Sahand Shokri
  • Behzad Shokati Beyrag
  • Amin Emadi
  • Rashid Hajivand Dastgerdi

External Organisational units

  • Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, Tehran, Iran
  • Southwest Jiaotong University
  • University of Tehran
  • Department of Chemistry
  • Pajoohesh Consulting Engineers
  • AGH Wissenschaftlich-Technische Universität

Abstract

In modern urbanized areas, the increasing demand for underground structures has led to an increase in the number of tunnelling projects in soft and shallow grounds. Tunneling in such conditions poses significant challenges, primarily due to the ground's low shear capacity and high deformation potential, leading to tunnel face instability and surface settlement. Accurate calculation of surface settlement is crucial in order to prevent probable damage to nearby structures. Consequently, various field measurement techniques and analytical solutions have been developed to estimate the maximum surface settlement resulting from tunneling activities in urban areas. These methods provide valuable insights to mitigate the risks associated with excessive settlement, ensuring the integrity and safety of surrounding infrastructure. Therefore, this study employs the numerical approach to gain a comprehensive understanding on surface settlement and the tunneling operation with tunnel boring machines. The analysis considers various performance parameters, including applying pressure around the shield, grout pressure, face pressure, parameters of machine advancement, and shield conicity. The aim of this research is to compare the results obtained from the numerical model with those obtained from precision instruments. Firstly, a comprehensive background on the importance of the considered subject is outlined, and the procedure of numerical modeling is elaborated in detail which is followed by outputs, comparisons, discussion and conclusions. The findings of this study demonstrate that the difference between surface settlement obtained from the results of instrumentation and numerical modeling for the eight investigated sections was an average of 11%, which was deemed negligible. These results highlight the potential of three-dimensional modeling and simulation techniques to support accurate estimation of surface settlement in tunneling operations, thereby minimizing potential damage to the surrounding structures. The reliable assumptions and simulation techniques used in this research can be useful for future tunneling projects to reduce the construction costs.

Details

Original languageEnglish
Pages (from-to)66-79
Number of pages14
JournalEngineering and applied science research
Volume51.2024
Issue number1
DOIs
Publication statusPublished - 10 Jan 2024