TBM–Block Interaction during TBM Tunneling in Rock Masses: Block Classification and Identification

A new block-classification method for tunnel construction using a tunnel-boring machine (TBM) to capture the geometrical and mechanical transformation of rock blocks in the course of TBM excavation is proposed in this paper. The machine–block interaction is interpreted by dividing the joint blocks into blocks influenced by TBM excavation and blocks uninfluenced by TBM excavation. The influenced blocks are categorized further as contacting or noncontacting blocks according to whether they are in contact with the TBM. The contacting blocks include the front block, the corner block, and the rear block, based on the spatial location of blocks with respect to the cutterhead. Different types of blocks have distinct kinematic and mechanical characteristics. The sizes and shapes evolve, and the categories may be changed for rock blocks during excavation. The identification algorithms for influenced blocks and three types of contacting blocks are presented. Finally, a simple example considering a double-shield TBM tunnel excavation is used to illustrate the effectiveness of the new block-classification approach to guide TBM tunneling. The new classification approach will be helpful in evaluating the block removability and the possibility of cutterhead clogging and to shield blockage during tunneling with a TBM.

[1]  Nuh Bilgin,et al.  The performance of a TBM in a squeezing ground at Uluabat, Turkey , 2012 .

[2]  Giovanni Battista Barla,et al.  Engineering geology of Alpine Tunnels: past, present and future , 2010 .

[3]  Janosch Stascheit,et al.  Computational Simulation of Mechanized Tunneling as Part of an Integrated Decision Support Platform , 2011 .

[4]  John A. Hudson,et al.  Discontinuities and rock mass geometry , 1979 .

[5]  Zixin Zhang,et al.  Object-oriented modeling for three-dimensional multi-block systems , 2013 .

[6]  Georg Anagnostou,et al.  On the feasibility of TBM drives in squeezing ground , 2006 .

[7]  H. Copur,et al.  Estimating torque, thrust and other design parameters of different type TBMs with some criticism to TBMs used in Turkish tunneling projects , 2014 .

[8]  Marco Barla,et al.  Rock Slide Simulation with the Combined Finite-Discrete Element Method , 2012 .

[9]  G. Barla,et al.  Tbm Tunnelling In Difficult Ground Conditions , 2000 .

[10]  Richard E. Goodman,et al.  Vector Analysis of Keyblock Rotations , 1996 .

[11]  Pinnaduwa Kulatilake,et al.  A new stereo-analytical method for determination of removal blocks in discontinuous rock masses , 2003 .

[12]  G. Ma,et al.  A rational and realistic rock mass modelling strategy for the stability analysis of blocky rock mass , 2014 .

[13]  Yilan Kang,et al.  Modeling of the thrust and torque acting on shield machines during tunneling , 2014 .

[14]  Z Zhang,et al.  A new methodology of block system construction and visualization for three-dimensional block-group analysis , 2011 .

[15]  Richard E. Goodman,et al.  Block theory and its application to rock engineering , 1985 .

[16]  Giovanni Battista Barla,et al.  A Completely 3D Model for the Simulation of Mechanized Tunnel Excavation , 2012, Rock Mechanics and Rock Engineering.

[17]  Johannes L. Wibowo.  Consideration of secondary blocks in key-block analysis , 1997 .

[18]  Zhen Zhang,et al.  Stability analysis of rock blocks around a cross-harbor tunnel using the improved morphological visualization method , 2015 .

[19]  Georg Anagnostou,et al.  Thrust force requirements for TBMs in squeezing ground , 2010 .

[20]  P. Warburton.  Vector stability analysis of an arbitrary polyhedral rock block with any number of free faces , 1981 .

[21]  Guowei Ma,et al.  Extended key block analysis for support design of blocky rock mass , 2014 .

[22]  Felix Nagel,et al.  Numerical Simulation of Interactions between the Shield-Supported Tunnel Construction Process and the Response of Soft Water-Saturated Soils , 2012 .

[23]  A. R. Yarahmadi Bafghi,et al.  The key‐group method , 2003 .

[24]  Herbert H. Einstein,et al.  Characterizing rock joint geometry with joint system models , 1988 .

[25]  Georg Anagnostou,et al.  Tunnel boring machines under squeezing conditions , 2010 .

[26]  M. Mauldon.  PROBABILITY ASPECTS OF THE REMOVABILITY AND ROTATABILITY OF TETRAHEDRAL BLOCKS , 1990 .

[27]  Qinghua Lei,et al.  A Morphological Visualization Method for Removability Analysis of Blocks in Discontinuous Rock Masses , 2013, Rock Mechanics and Rock Engineering.

[28]  Jun Xiao,et al.  Block theory on the complex combinations of free planes , 2012 .