Structural performance of final lining according to the rock load shape

The purpose of this study is to analyze the structural performance of the lining according to the magnitude as well as shape of rock load. Four cases of rock load shape were applied on the final lining (concrete lining) to perform structural analysis using beam spring model. This study includes two contents; firstly, the stability of the lining was analyzed using capacity diagrams. Secondly, the serviceability of the lining was analyzed using the cracked hinge model. While assessing the stability of the lining, FS = 2.45 was used according to LRFD specifications. The stress-crack opening relationship, represented by g(w) function, was used to assess the serviceability of the lining. The critical parameters used in this study are the K0 condition, load direction and application of the wedge load. Based on the results obtained after analysis, it was concluded that the K0 condition could change the thrust force-bending moment relationship which affects the stability and serviceability of the lining. Rock load in vertical direction affected the lining more than that in horizontal direction. Lastly, the development of wedge load proved to be more adverse than the application of larger uniform rock load on the lining.

[1]  John Forbes Olesen,et al.  Fictitious Crack Propagation in Fiber-Reinforced Concrete Beams , 2001 .

[2]  Rolf Stadelmann,et al.  Design in tunnelling, structural design methods for the inner lining , 2009 .

[3]  A. Jones.  10 – Rock Mechanics and Rock Engineering , 1989 .

[4]  Robert Galler,et al.  Long-term deterioration of lining in tunnels , 2013 .

[5]  M. Savoia,et al.  Concrete crack reduction in tunnel linings by steel fibre-reinforced concretes , 2013 .

[6]  Nick Barton,et al.  Engineering classification of rock masses for the design of tunnel support , 1974 .

[7]  Nobuharu Isago,et al.  Numerical approach for design of tunnel concrete lining considering effect of fiber reinforcements , 2004 .

[8]  Jianhang Liu,et al.  Assessment service state of tunnel structure , 2012 .

[9]  Vincent Labiouse,et al.  Analysis of the evolution of road tunnels equilibrium conditions with a convergence–confinement approach , 2010 .

[11]  Moon Kyum Kim,et al.  Prediction of ground load by performing back analysis using composite support model in concrete lining design , 2015 .

[12]  Andreas J. Kappos,et al.  Practical nonlinear analysis of unreinforced concrete tunnel linings , 2014 .

[13]  Mohammad Ali Moridi,et al.  Time-dependent behavior of tunnel lining in weak rock mass based on displacement back analysis method , 2013 .

[14]  H. Yoo,et al.  Evaluation of rock load based on critical shear strain concept on tunnels , 2013 .

[15]  Mark S. Diederichs,et al.  Mechanical analysis of circular liners with particular reference to composite supports. For example, liners consisting of shotcrete and steel sets , 2009 .