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Berilgen M. M., Aktaş Ş.

8. Uluslararası Geoteknik Sempozyumu, İstanbul, Turkey, 13 - 15 November 2019, pp.12-19

  • Publication Type: Conference Paper / Full Text
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.12-19
  • Yıldız Technical University Affiliated: Yes


Although general opinion stability and deformation problems are not expected during excavations in rock units, this expectation is not valid for soft and multi-jointed-rock units. This requires the design of a supporting system that does not lead to stability and deformation problems during excavations in soft and multi-jointed-rock units. In order for this support system to meet the design expectations, the analysis for the design should be based on the principles of rock mechanics. In this context, idealizing the behavior of the rock environment to represent the field and developing the design according to the rock unit emerges as the current engineering approach. In this paper, it is aimed to investigate the effect of fracture orientations on excavation behavior in deep excavations in weak rock units with joint fractures by numerical analysis. For this purpose, a hypothetical deep excavation was taken into consideration, and the Jointed Rock Constuction Model, in which rock joints could be taken into account, was carried out numerically. In these analyzes performed on a hypothetical excavation geometry, firstly the effect of rock joint orientation on displacement and safety number was determined by sensitivity analyzes and then stress strain and stability analyzes were performed for incremental excavation depths for different dip angles. The data obtained from these analyzes were plotted with the number of depth and the relationship between safety and depth. According to these results, it was seen that the plunging angle significantly affected the excavation stability depending on the depth of excavation.