Zayıf ve Sıkışan Kaya Kütlesinde Açılan Bir Tünel için Rijit Destek Sistemi Çözümü (T34-GT2 Tüneli, Ankara-İstanbul YHT Projesi)

Year 2025, Volume: 49 Issue: 1, 105 - 120, 11.06.2025

Evren Poşluk , Servet Karahan , Candan Gökçeoğlu

https://doi.org/10.24232/jmd.1666024

Abstract

Bu çalışmaya konu olan T34-GT2 Tüneli, 4,5 m genişliğinde 5 m yüksekliğinde olup, Ankara-İstanbul Hızlı Tren Projesi kapsamında T34 Tünelinde (km: 229+360-231+578) yolcu güvenliğini sağlamak amacıyla inşaa edilmiştir. Tünel 25 m uzunluğunda ve tamamı Karbonifer-Permiyen yaşlı meta-kırıntılı birimler içindedir. Tünel yaklaşık 650 eğimli normal fay tarafından kesilmektedir. Bu fay boyunca bir zon olarak zayıf ve sıkışan kaya özelliğinde meta-kırıntılılar bulunmaktadır. Bu tür kaya ortamları, tünel destek sistemi tasarımı açısından kritik öneme sahiptir. Benzer kaya koşullarında açılan tünellerde ayna ve tavan stabilite sorunlarının yanında ciddi deformasyonların olduğu bilinmektedir. Bu nedenle bu çalışmada tünelcilik açısından özel problemler içeren T34-GT2 Tünelinde bulunan fay zonuna odaklanılmış en uygun destek sisteminin analizlerle ortaya konulması amaçlanmıştır. Bu amaçla tünelin sıkışma potansiyeli belirlenmiş, hızlı kazı, güçlü destek, düşük deformasyon prensiplerine dayanan rijit destek sistemi tasarlanmıştır. Tasarlanan destek sistemi sayısal analiz yöntemleri kullanarak detaylandırılmış ve elde edilen sonuçlar tünel kazı ve destek aşamalarında dikkate alınmıştır. Ardından analiz sonuçları tünelde gerçekleşen deformasyonlarla kıyaslanmıştır. Sonuç olarak, sayısal analizler ile tünelde gerçekleşen deformasyonların birbirine yakın olduğu ve önerilen rijit destek sisteminin benzer kaya koşullarında uygulanabilir bir yaklaşım olduğu belirlenmiştir.

Keywords

Sayısal analiz , Sıkışma , Tünel güvenliği , Zayıf kaya

Rigid Support System Solution for a Tunnel in Weak and Squeezing Rock Mass (T34-GT2 Tunnel, Ankara-Istanbul YHT Project)

Abstract

The T34-GT2 Tunnel, the subject of this study, is 4.5 m wide and 5 m high and was constructed within the scope of the Ankara-Istanbul High Speed Train Project to ensure passenger safety in the T34 Tunnel (km: 229+360-231+578). The tunnel is 25 m long and is entirely located within the Carboniferous-Permian metaclastic units. The tunnel is istersected by a normal fault with an inclination of approximately 650. There are metaclastics with weak and squeezing rock characteristics along the fault zone.It is known that there are serious deformations in addition to face and roof stability problems in tunnels excavated under similar rock conditions. Therefore, this study focuses on the fault zone in the T34-GT2 Tunnel, which has special problems in terms of tunneling, and aims to reveal the most suitable support system with analyses. For the purpose of the study, the squeezing potential of the tunnel was determined and a rigid support system based on the principles of fast excavation, strong support, and low deformation was designed. The designed support system was detailed using numerical analysis methods and the obtained results were considered during the tunnel excavation and support stages. Then, the analysis results were compared with the deformations in the tunnel. As a result, it was determined that the deformations in the tunnel were close to each other with the numerical analysis and the proposed rigid support system was an applicable approach in similar rock conditions.

Keywords

Numerical analysis , Squeezing , Tunnel safety , Weak rock

References

• AFAD. (2025). Türkiye deprem tehlike haritaları [Earthquake hazard maps of Turkey]. Retrieved from http://tdth.afad.gov.tr.
• Akgün, H., Muratlı, S. W., & Koçkar, M. K. (2014). Geotechnical investigations and preliminary support design for the Geçilmez tunnel: A case study along the Black Sea coastal highway, Giresun, northern Turkey. Tunnelling and Underground Space Technology, 40, 277–299.
• Aksoy, C. O., Ogul, K., Topal, I., Ozer, S. C., Ozacar, V., & Posluk, E. (2012). Numerical modeling of non-deformable support in swelling and squeezing rock. International Journal of Rock Mechanics and Mining Sciences, 52, 61–70.
• Aksoy, C. O., Uyar, G. G., Posluk, E., Ogul, K., Topal, I., & Kucuk, K. (2016). Non-deformable support system application at tunnel-34 of Ankara-Istanbul high-speed railway project. Journal of Rock Mechanics and Mining Sciences, 58(5), 869–886.
• Apaydin Poşluk, E., & Koral, H. (2013). Bozüyük (Bilecik)-Oklubali (Eskişehir) arasının Neojen stratigrafisi ve yapısal özellikleri. İstanbul Yerbilimleri Dergisi, 26(2), 83-103.
• Aygar, E. B. (2020). Evaluation of the new Austrian tunnelling method applied to Bolu tunnel’s weak rocks. Journal of Rock Mechanics and Geotechnical Engineering, 12(3), 541–556.
• Aygar, E. B., & Gokceoglu, C. (2020). Problems encountered during a railway tunnel excavation in squeezing and swelling materials and possible engineering measures: A case study from Turkey. Sustainability, 12, Article 1166.
• Aygar, E. B., & Gokceoglu, C. (2021). A special support design for a large-span tunnel crossing an active fault (T9 Tunnel, Ankara–Sivas High-Speed Railway Project, Turkey). Environmental Earth Sciences, 80, Article 37.
• Aygar, E. B., Karahan, S., & Gokceoglu, C. (2024). Tunneling problems in weak rock conditions under shallow overburden and comparison between full-face excavation and sequence excavation methods. Geomechanics and Geoengineering, 19(4), 668–688.
• Barton, N. R., Lien, R., & Lunde, J. (1974). Engineering classification of rock masses for the design of tunnel support. Rock Mechanics, 6(4), 189–239.
• Barton, N., Løset, F., Lien, R., & Lunde, J. (1980). Application of the Q-system in design decisions. In Bergman, M. (Ed.), Subsurface Space (Vol. 2, pp. 553–561). New York: Pergamon.
• Bieniawski, Z. T. (1973). Engineering classification of jointed rock masses. Transactions of South African Institution of Civil Engineers, 15, 335–344.
• Bieniawski, Z. T. (1976). Rock mass classification in rock engineering. In Bieniawski, Z. T. (Ed.), Exploration for Rock Engineering: Proceedings of the Symposium (Vol. 1, pp. 97–106). Cape Town: Balkema.
• Bieniawski, Z. T. (1989). Engineering Rock Mass Classifications. New York: Wiley.
• Cao, C., Shi, C., Lei, M., Yang, W., & Liu, J. (2018). Squeezing failure of tunnels: A case study. Tunnelling and Underground Space Technology, 77, 188–203.
• Cheng, X. (2017). Discussion on the large deformation law of Muzhailing tunnel in Lanhai Expressway. World Construction, 6(2), 22–25.
• Dalgic, S. (2002). Tunneling in squeezing rock: The Bolu tunnel Anatolian Motorway, Turkey. Engineering Geology, 67(1–2), 73–96.
• Das, R., Singh, P. K., Kainthola, A., & Panthee, S. (2017). Numerical analysis of surface subsidence in asymmetric parallel highway tunnels. Journal of Rock Mechanics and Geotechnical Engineering, 9, 170–179.
• Fenner, R. (1938). Untersuchungen zur erkenntnis des gebirgsdrucks. Glückauf, 74(32), 681–695.
• Hoek, E. (2001). Big tunnels in bad rock. Journal of Geotechnical and Geoenvironmental Engineering, 127(9), 726-740.
• Hoek, E. (2012). Rock support interaction analysis for tunnels in weak rock masses. Retrieved from https://www.rocscience.com/documents/pdfs/rocnews/winter2012/Rock-Support-lnteraction-Analysis-for-Tunnels-Hoek.pdf
• Hoek, E., & Guevara, R. (2009). Overcoming squeezing in the Yacambú-Quibor tunnel, Venezuela. Rock Mechanics and Rock Engineering, 42(2), 389–418.
• Hoek, E., & Marinos, P. (2000). Predicting tunnel squeezing problems in weak heterogeneous rock masses. Tunnels and Tunnelling International, 32, 45–51.
• Hoek, E., & Marinos, P. G. (2010). Tunnelling in overstressed rock. Proceedings of the Regional Symposium of the International Society for Rock Mechanics, EUROCK 2009: Rock Engineering in Difficult Ground Conditions – Soft Rocks and Karst, Dubrovnik, Cavtat, 29–31 October 2009, Taylor and Francis Group, London, pp. 49–60.
• İncecik, M., & Poşluk, E. (2018). Tunnel T26 on the Ankara–Istanbul high-speed rail route–Tunnelling under difficult conditions. Geomechanics and Tunnelling, 11(5), 434–440.
• ISRM. (1981). Suggested methods: Rock characterization, testing, and monitoring. In E. T. Brown (Ed.), Permagon Press. London.
• Jethwa, J., Singh, B., & Singh, B. (1984). Estimation of ultimate rock pressure for tunnel linings under squeezing rock conditions – a new approach. Design and Performance of Underground Excavations: ISRM Symposium, Cambridge, UK, 3–6 September 1984, pp. 231–238.
• Karahan, S., Posluk, E., Büyükdemirci, F. B., & Gökçeoğlu, C. (2025). Re-design of a railway tunnel intersected by surface rupture of the Erkenek fault segment during the 6 February 2023 Pazarcık (Mw 7.7) Earthquake (Türkiye). Bulletin of Engineering Geology and the Environment, 84, Article 198.
• Karayolları Genel Müdürlüğü (KGM). (2013). Araştırma mühendislik hizmetleri teknik şartnamesi. Teknik Araştırma Dairesi Başkanlığı (T.A.D.B).
• Koçkar, M. K., & Akgün, H. (2003). Methodology for tunnel and portal support design in mixed limestone, schist, and phyllite conditions: A case study in Turkey. International Journal of Rock Mechanics & Mining Sciences, 40, 173–196.
• Mhanna, M., & Hussein, H. H. (2024). Analysis of squeezing‐induced failure in a water tunnel and measure of rehabilitation: A case study of Tishreen Tunnel, Syria. Deep Underground Science and Engineering, 1, 1–13.
• NGI (Norwegian Geotechnical Institute). (2015). Using the Q-system: Rock mass classification and support design (Handbook).
• ÖNORM B 2203. (1994). Untertagebauarbeiten–Werkvertragsnorm. Wien: Österreichisches Normungsinstitut.
• Panet, M., & Sulem, J. (2022). Convergence-confinement method for tunnel design. Gewerbestrasse, 1–151.
• Panthi, K. K., & Nilsen, B. (2007). Predicted versus actual rock mass conditions: A review of four tunnel projects in Nepal Himalaya. Tunnelling and Underground Space Technology, 22(2), 173–184.
• Poşluk, E. (2024). T26 Tünelindeki sıkışan kayalarda tünel açma makinesi (TBM) ile klasik kazı yöntemlerinin karşılaştırılması. Doktora Tezi, İstanbul Üniversitesi-Cerrahpaşa Lisans Üstü Eğitim Enstitüsü, 304 s., İstanbul.
• Poşluk, E., & Korkanç, M. (2017). Yüksek Hızlı Tren Tünellerinde Tünel Emniyet Modellemeleri: Ankara-İstanbul Yüksek Hızlı Tren Projesi Tüneli No. 26 Örneği. Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi, 6(2), 642–652.
• Poşluk, E., & Korkanç, M. (2018). Difficulty on performance prediction of excavation with machine in weak rocks. Journal of Geological Engineering, 42(2), 143–158.
• Poşluk, E., & Korkanç, M. (2018). Zayıf Kayalarda Makine ile Kazı Performans Tahminindeki Zorluklar. Jeoloji Mühendisliği Dergisi, 42(2), 143–158.
• Rabcewicz, L. v. (1964a). The New Austrian Tunnelling Method, Part One. Water Power, 453–457.
• Rabcewicz, L. v. (1964b). The New Austrian Tunnelling Method, Part Two. Water Power, 511–515.
• Rabcewicz, L. v. (1965). The New Austrian Tunnelling Method, Part Three. Water Power, 19–24.
• Rabcewicz, L. v., & Golser, J. (1973). Principles of dimensioning the supporting system for the “New Austrian Tunnelling Method.” Water Power, 88–93.
• RocScience. (2020). Phase2 8.0 Excavation & Support Design.
• Satıcı, Ö., & Topal, T. (2015). Tünel açma yöntemlerinin mühendislik jeolojisi ve kaya sınıflama sistemleri ile değerlendirilmesi. Jeoloji Mühendisliği Dergisi, 39(1), 45–57.
• Singh, B., Jethwa, J. L., Dube, A. K., & Singh, B. (1992). Correlation between observed support pressure and rock mass quality. Tunnelling and Underground Space Technology, 7, 59–74.
• Şentürk, K., & Karaköse, C. (1981). Orta Sakarya bölgesinde Liyas öncesi ofiyolitlerinin ve mavi şistlerinin oluşumu ve yerleşmesi. Türkiye Jeoloji Kurumu Bülteni, 24(1), 1–11.
• Terzaghi, K. (1946). Rock defects and loads on tunnel supports. In R. V. Proctor & T. L. White (Eds.), Rock Tunnelling with Steel Supports (Vol. 1, pp. 17–99). Youngstown, OH: Commercial Shearing and Stamping Company.
• TSI. (2008). Technical specification of interoperability relating to ‘Safety in Railway Tunnels’ in the trans-European conventional and high-speed rail system.
• UIC (International Union of Railways). (2003). Safety in Railway Tunnels (Code 779-9).
• Yedigöze Tİnşaat A.Ş. (2015). T34-GT2 Tüneli hesap raporu. (Yayımlanmamış).
• Zou, J., Chen, G., & Qian, Z. (2019). Tunnel face stability in cohesion-frictional soils considering the soil arching effect by improved failure models. Computers and Geotechnics, 106, 1–17.