1999 Volume 9 Pages 195-200
TBM wall image processing system has been developed to take tunnel wall images by ccd cameras during TBM excavation and to analyze the geological structure of the tunnel using the images. The ccd cameras are fixed to the TBM machine, and tunnel wall surface is photographed continuously with the strokes of thrust jacks. Tunnel wall images will be combined and translated in a personal computer, and image maps will be printed out. Then, strike, dip and aperture of discontinuities are calculated by the geological analysis program. By applying this system to TBM excavation, the geological condition of tunnel wall can be grasped visually and the stability of tunnel under the influence of discontinuities can be estimated accurately. This system is applied to TBM pilot tunnel of Hamamatsu Tunnel East, Second Tomei Expressway, and satisfactory results are obtained.
