Investigation of Shallow Tunneling Method (STM) for Metro Station Construction in Weak Soils and Low Overburden (Case Study: Esteghlal Metro Station in Shiraz)

Document Type : Original Article

Authors
1 M.Sc. Student, Department of Civil Engineering, Kazerun Branch, Islamic Azad University, Kazerun, Iran.
2 Assistant Professor, Department of Civil Engineering, Yasuj Branch, Islamic Azad University, Yasuj, Iran.
3 Assistant Professor, Departmnt of Civil Engineering and Architecture, Yasuj Branch, Islamic Azad University, Yasuj, Iran.
Abstract
Always considering risk, cost and time reduction, the best method for tunnel excavation should be selected and implemented. Choosing the optimal method for tunnel digging requires full knowledge of tunnel digging methods and the parameters affecting them. project conditions and existing infrastructure, project completion time, and environmental issues. Also, the prediction and control of settlement is of significant importance in urban areas, both from the point of view of safety and from the economic point of view. In recent years, the use of working tunnels at a shallow depth has been used to dig underground spaces, including subway stations and similar spaces in different soils, which is popular in urban spaces due to the lack of disruption to traffic. Tunneling at a shallow depth and in weak soil is called STM (Shallow Tunneling Method).Using STM in urban spaces it should be accurately evaluated in terms of settlement on the ground surface and its effects on surface mining structures. In order to check each of the methods, three-dimensional numerical modeling will be used. The purpose of numerical modeling by 3D method is to accurately check the amount of settlement during execution and to determine the best execution method with the least amount of settlement. Different methods with different classifications for drilling have been examined and finally the method that can be used in this study is presented and the best method with the least amount of settlement is introduced as the best option.
Keywords

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