Study of the Tunnel Crown behavior Under the Influence of Near Field Earthquakes with Finite Element Method

Document Type : Research Paper

Authors

1 M.Sc. of Geotechnical Engineering, Department of Civil Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran.

2 Ph.D. Candidate, Department of Civil Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran

Abstract

Today, the use of underground structures and their numerous uses in urban and interurban transportation has been found to be of great importance and has become one of the topics discussed by engineers in the field of construction and civil engineering. One of the issues that have attracted the attention of the researchers in these structures is the resistance of these structures to the rejection of dynamic loads. Therefore, in the present article, the seismic behavior of the tunnel under the earthquake record in the near field has been studied with regard to overhead and overhead. To analyze this research, the seismic behavior of tunnel line 2 of Tabriz city trains was selected and using the abacus software and available geotechnical reports, the 2nd line of Tabriz city trains was studied. The results of this study indicate that, in case of overturning, the amount of deformation and strain in the tunnel crown increases, this increase is proportional to the earthquake record. The results also show that the behavior of the tunnel in case of overhead operation in relation to the non-overhead state is not under the earthquake record of the near-frontier zone, which is sensitive to soil layering, and the variation of the tunnel crown under both acceleration maps of Bam and Varzaghan in all sections of the Earth's crust is close to It has been. The results also indicate that on the route of line 2 of the city of Tabriz, despite the change in the characteristics of the soil mass in the path, the tunneling behavior has little sensitivity to soil layering in the path and if the tunnel is located at a depth of 22 meters from the ground level under the earthquake record There is not much deformation in the crown of the tunnel.

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