Stability analysis, displacement monitoring and justification of the critical sections of the Konak Tunnel


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Jeoloji Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2015

Öğrenci: KADİR YERTUTANOL

Danışman: HALUK AKGÜN

Özet:

The main focus of this research is numerical analysis and preliminary support design for the critical sections of the twin tube Konak Tunnel that was constructed in a highly populated area in Konak, İzmir. The displacements of the tunnel were monitored and justified by comparing with the results of the numerical analyses. The stability of the tunnel exit portal and associated slopes, which is one of the most challenging sections of the project, was analyzed as well. In study area, volcanics, pyroclastics and some sedimentary deposits (sandstone, mudstone and conglomerate) often intertongue with each other especially in the exit portal area. The accurate determination of the shear strength and deformation parameters of these units is important for the assessment of portal slope stability and support design and displacement predictions in the tunnel design. Rock mass classification systems, namely, RMR, Q system and GSI, have been employed to obtain the rock mass shear strength and deformation parameters. Stress analysis around the tunnel openings has been done through employing 2D finite element analysis for inspecting the tunnel support design and the vertical displacement in the critical sections and five different measurement points. The results of the finite element analysis have been controlled and correlated with the results of monitored vertical displacements. Consequently, when the monitoring points on the critical sections are evaluated individually, 70 % of the points ensure the predicted displacement limits and only 12.5 % of the displacements mismatch ratio is higher than the 50 %. Moreover both the support system elements and the rock