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Experimental study on the longitudinal load transfer of a shallow tunnel depending on the deformation tunnel face (II)

얕은 터널의 굴진면 변형에 따른 종방향 하중전이 특성에 대한 실험적 연구(II)

  • Kim, Yang Woon (Ajou University, Dept. of Civil and Transportation Eng) ;
  • Lee, Sang Duk (Ajou University, Dept. of Civil and Transportation Eng)
  • 김양운 (아주대학교 건설교통 시스템공학과) ;
  • 이상덕 (아주대학교 건설교통 시스템공학과)
  • Received : 2016.09.13
  • Accepted : 2016.09.28
  • Published : 2016.09.30

Abstract

In recent years, the use of underground spaces becomes more frequent and the demands for urban tunnels are rapidly increasing. The urban tunnels constructed in the ground with a shallow and soft cover might be deformed in various forms on the face, which would lead, the tunnels to behavior 3-dimensionally, which may have a great impact on the longitudinal load transfer. The tunnel face might deform in various forms depending on the construction method, overburden and the heterogeneity of the ground. And accordingly, the type and size of the distribution of the load transferred to the ground adjacent to the tunnel face as well as the form of the loosened ground may appear in various ways depending on the deformation form of the tunnel face. Therefore, in this study was conducted model tests by idealizing the deformation behavior of the tunnel face, that were constant deformation, the maximum deformation on the top and the maximum deformation on the bottom. And the test results were analyzed focusing on the deformation of the face and the longitudinal load transfer at the ground above the tunnel. As results, it turned out that the size and the distribution type of the load, which was transferred to the tunnel as well as the earth pressure on the face were affected by the deformation type of the face. The largest load was transferred to the tunnel when the deformation was in a constant form. Less load was transferred when the maximum deformation on the bottom, and the least load was transferred when the maximum deformation on the top. In addition, it turned out that, if the cover became more shallow, a longitudinal load transfer in the tunnel would limited to the region close to the face; however, if the cover became higher than a certain value, the area of the load transfer would become wider.

References

  1. Chambon, P., Corte, J.F. (1994), "Shallow tunnels in cohesionless soil : stability of tunnel face", J. of Geotech. Engng. Vol. 120, No.7, pp. 1148-1165. https://doi.org/10.1061/(ASCE)0733-9410(1994)120:7(1148)
  2. Idinger, G., Aklik, P., Wu, W., Borja, R.I. (2011). Centrifuge model test on the face stability of shallow tunnel. Acta Geotechnica 6, No. 2, pp. 105-117. https://doi.org/10.1007/s11440-011-0139-2
  3. Lee, S.D. (2013), "Tunnel Mechanics", CIR publication, pp. 253-360.
  4. Ohde, J. (1938), "Zur Theorie des Erddrucks unter besonderer Beruecksichtigung der Erddruckverteilung", Die Bautechnik, p. 176.
  5. Terzaghi, K. (1936), "Stress distribution in dry and in saturated sand above a yielding trap-door", Proc. 1st Int. Conf. Soil Mech. Found. Engng., Cambridge, Vol. 1, pp. 307-311.