Zayıf kaya kütlelerinde açılan tünellerde ampirik ve mümerik yöntemlerle duraylılık analizi
Zayıf kaya kütlelerinde açılacak tünellerin tasarımı, mühendislik jeolojisi açısından bazı zorluklar sunmaktadır. Tasarım aşamasında yapılacak küçük bir hata, kazı aşamasında maliyeti yüksek ve zaman alıcı sorunlara yol açabilmektedir. Bu tür ciddi sorunlarla karşılaşmamak için zayıf kaya kütlelerinde açılacak tünellerin, tasarım aşamasında, en uygun ve ekonomik kazı yöntemine göre projelendirilmesi gerekmektedir. Bu çalışmada, Cankurtaran (Hopa-Artvin) tünelinin güzergahında yüzeylenen Paleosen yaşlı Şenkaya Sırtı formasyonu’na ait ince tabakalı marnların duraylılığı, ampirik ve nümerik yöntemler kullanılarak incelenmiştir. İlk önce, ISRM (1981) tanımlama kriterleri esas alınarak marnların içerdiği süreksizlerin özellikleri ve kaya malzemesinin jeomekanik özellikleri belirlenmiştir. İkinci aşamada, marnlar RMR, Q ve GSI sistemleri ile sınıflandırılmış ve kütle özellikleri tespit edilmiştir. Son aşamada ise marnlarda açılması planlanan tünelin duraylılığı, Singh vd. (1992), Goel vd. (1995), Bhasin ve Grimstad (1996) kriterleri ve Sonlu Eleman Yöntemi (FEM) yardımıyla araştırılmıştır. Yapılan analizler sonucunda güvenlik sayısı değerinin 0.08 ile 1.43 arasında değiştiği ve tünelde duraysızlık sorunuyla karşılaşma riskinin olabileceği sonucuna varılmıştır.
Stability analyses of tunnels excavated in weak rock masses using empirical and numerical methods
In terms of geological engineering, tunnel design in weak rock masses presents some challenges. A small misinterpretation in the design stages can lead to costly and time-consuming problems at the construction phases. To avoid serious problems of these kinds, tunnels excavated in weak rock masses should be projected with the most suitable and economical excavation method in design stage. In this study, stability of the thin-bedded marls belong to Paleocene aged Şenkaya Sırtı formation, outcropped on the route of Cankurtaran (Hopa-Artvin) tunnel, was investigated using empirical and numerical methods. Firstly, the properties of the discontinuities in the marls and geomechanical parameters of intact rock material were determined based on the description criteria of ISRM (1981). In the next stage, marls were classified by using the RMR, Q and GSI systems and rock mass properties were determined. In the final stage, the stability of the tunnel, planned to be excavated in the marls, was investigated by using the criterion of Singh et al. (1992), Goel et al. (1995), Bhasin and Grimstad (1996) and Finite Element Method (FEM). As a result of the analyses, it was concluded that the factor of safety value varies between 0.08 and 1.43 and there may be a risk of instability problem in the tunnel.
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- ISSN: 1016-9172
- Başlangıç: 1977
- Yayıncı: TMMOB Jeoloji Mühendisleri Odası
Sayıdaki Diğer Makaleler
Zayıf kaya kütlelerinde açılan tünellerde ampirik ve mümerik yöntemlerle duraylılık analizi
Örneklemeden Rapor Etmeye Adım Adım Maden Kaynak Tahmini
Yusuf Ziya ÖZKAN, Mehmet Ali AKBABA
Zayıf Kaya Kütlelerinde Açılan Tünellerde Ampirik ve Nümerik Yöntemlerle Duraylılık Analizi