Abstract:

Weathered granite residual usually causes enormous risks to the shield tunneling in urban Metro construction. Therefore, detection must be carried out in advance along the tunnel alignment, so as to ensure the successful driving of shield through the formation with granite boulders. Compared to the traditional drilling method, seismic method has obvious advantages such as less environmental interference, high efficiency, wide coverage and low cost. In the paper, the applicability of common seismic detection methods is studied on the basis of the characteristics of granite formation and urban environment in south China. Conclusion is drawn that the shallow seismic reflection method is effective in boulder detection and that the detection accuracy can be improved by Swave detection. The paper can provide reference for the detection of boulders in future works.

Key words: shield tunneling, granite, boulder, seismic method, detection