Stability evaluation system on tunnel face and its field applicability

本研究对三维摄影测量技术作为隧道工作面稳定性评价系统的基础技术及其现场适用性进行了精度验证。摄影测量是自动测量三维位置关系的技术。也就是说，从不同的位置拍摄被摄体，并且由计算机立体地观看和处理多个片断的照片。利用摄影测量技术，本研究设计的测量系统可以方便地测量整个工作面的变形行为。在摄影测量中，需要测量控制点。然而，在隧道工作面设置测量控制点是危险的。然后，避开工作面的工作，将其作为常规测量断面上远离面的测点，在面平面上新设半点。然后，用9 mm厚的聚苯乙烯泡沫版再现巷道工作面的性态，验证了摄影测量的位移精度。通过验证，得出以下结论：1)控制点和半点的位置对摄影测量的精度影响很大。2)阐明了在摄影测量中可以测量出1 mm精度的工作面变形行为。

This study carried out accuracy verification of the three-dimensional photogrammetry technology as basic technology of stability evaluation system of tunnel face and its field applicability. The photogrammetry is the technology which automatically measures the three-dimensional positional relation. That is to say, the subject is photographed from the position which differs, and the photograph of plural pieces is viewed and is processed by the computer stereoscopically. Using the photogrammetry, the measurement system aimed in this study conveniently measures deformation behavior of whole working face. In the photogrammetry, the measurement control point is required. However, it is dangerous to establish measurement control point on the tunnel face. Then, the work in the working face was avoided, and it was utilized as a measuring point on the conventional measurement cross section away from face plane, and in the face plane, semi-point should be newly establishedNext, The tunnel face behavior was reproduced using expanded polystyrene edition of the 9mm thickness, and the displacement accuracy of the photogrammetry was verified. As a result of the verification, following conclusions became clear1) The location in control point and semi-point strongly affects the accuracy of the photogrammetry. It is effective that it is placed in order to surround the range by the measurement for the accuracy improvement2) That working face deformation behavior of the 1mm accuracy could be measured in the photogrammetry clarified