Calculation of the stability pressure of the working face of the earth pressure balancing drilling machine using the 3D finite element limit analysis method (case study of Ahvaz metro Line 1 tunnel)

Document Type : Original Article

Authors
Mohammad Reza Entezr marne 1
Abbas Eslami Haghighat 2
Mohsen Haji Hassani 3
1 M.Sc., Student, Civil Engineering Department, Urmia University, Urmia, Iran.
2 Assistant Professor, Civil Engineering Department, Urmia University, Urmia, Iran.
3 Associate Professor, Mining Engineering Department, Urmia University, Urmia, Iran.
10.22034/road.2025.518012.2388
Abstract
In recent years, the use of mechanized drilling equipment, such as earth pressure balancing equipment, for tunnel excavation has become widespread. The proper design of these devices requires a careful study and examination of the soil mass around the excavation site. One of the important parameters in these studies is the working face stability pressure required to prevent the rupture of the soil mass around the excavation site due to collapse and uplift of the soil, which is applied to the soil mass by the drilling device. In this research, using the finite element limit analysis method in three-dimensional condition, the stability pressure of the tunnel working face of Line 1 of Ahvaz metro has been analyzed and investigated. This method is a combination of limit analysis and finite element meshing. The results obtained from this method in the collapse case are very accurate, so that the average of the upper and lower bounds obtained can be considered a good approximation of the actual load. These results show that the use of the 3D finite element limit analysis method to investigate the stability pressure of the working face well models the heterogeneity in the soil mass and, from an operational point of view, determines the safety range that the working face pressure can tolerate.
Keywords
Finite Element Limit Analysis, Working Face Stability Pressure, Limit Analysis, Lower Bound, Upper Bound
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