Suzuki TAKAHIRO

Development on setting method of three-dimensional correction alignment due to snake like motion

SUGIMOTO MITSUTAKA

 Shield tunneling method is a tunnel construction method to ensure the stability of the face by muck or slurry,excavate the ground by the disc cutter, and install the segmental lining inside the TBM.
 Tunnel alignments are determinned by taking into consideration the purpose,the operational conditions, the construction conditions, and so on, and are represented by horizontal alignments and vertical alignments.But since it is usual that the TBM 
daeviates from the planned alignment due to snake like motion,the control of the TBM is necessary to move back it to the planned alignment.However, the existing control method is to try to correct the current deviation by jack moment (jack pattern)
only.Since the entire correction alignment is not considered, it is impossible to perform shield control including methods other than jack moment. 
 Therefore, this research aims to develop a method to determine the correction alignment for returning the TBM to a planned alignment. The horizontal alignment is the projection of a three-dimensional alignment on a horizontal plane, while the 
vertical alignment can be obtained by projecting a three-dimensional tunnel alignment onto a vertical plane including the horizontal alignment. Each alignment can be dealt with two-dimensional problems. The correction alignment can be classified intofourtypes, based on direction angle change and position change between the correction start point and end point. The setting method for each type correction alignment were formulated. And combining the correction horizontal alignment and correction 
vertical alignment, the setting method of correction alignment in three-dimensional space was proposed. Furthermore, the validation of this method was examined by the application of this method.