Investigation Of Tunnel Boring Machinelandslide Relation In A Tunnel Excavating In A Complex Geological Condition: Bahçenurdağ Tunnel

Abstract

In recent years, Tunnel Boring Machine (TBM) has become increasingly more popular for long tunnel operations in terms of its characteristic of features of rapid and having low vibration. Twin-tubes railway tunnels are opened in between Bahçe (Osmaniye)-Nurdağ (Gaziantep) are also the longest railway tunnels in Turkey as the length of approximately 10 km. They started to be excavated from Nurdağ with using tunnel boring machines (TBM). Tunnels will be completed in intense slope debris and landslide which is caused by intense debris on Bahçe portal part. Therefore, geological environment of the study is one of the rare examples in terms of its complex engineering problems in the World. The construction of tunnel without subjecting to critical failure impacts depends on realistic geological and geotechnical characterization. For this reason, engineering parameters are determined by examining boreholes data in order to define geology of the study area. Consequently, the purpose of the thesis is investigation of the interaction effects landslide-TBM during construction on twin tubes tunnelling by performing 3D finite element analyses. MIDAS GTS NX software was used in stages of 3D numerical analyses. According to prepared 3D deformation results, TBM has negative effects on debris and landslide. Thus, inactivation of TBM tunnelling excavation for last 600 meters is vital with respect to safety and preventing economical loses. By taking into consideration its aims and goals, this thesis contributes the worldwide engineering geology and tunnel literature.