A MECHANICAL METHOD FOR DEFORMATION MEASUREMENT AND VISUALIZATION IN TUNNEL CONSTRUCTION

Deformation measurement is usually one of the key elements of measurement carried out in tunnel construction. A new mechanical method is proposed to measure the relative displacement between two points, and to visualize the results in real-time based on the concept of “On-site Visualization”. The mechanism of the method lies in that a rotational structure is used to translate the linear displacement into the rotation. Since the simple method performs in a mechanical way without using electricity, it would reduce the purchase&use cost to an acceptable degree.This paper presents the laboratory tests and a field experiment to verify the possibility and feasibility of the method. In the field experiment, the shotcrete cracks, the heave of invert and so on in the tunnel during construction were monitored by this method. The measured results are analyzed in comparison with those from Total Station, which shows the deformation of the tunnel during construction could be detected and visualized availably. Finally, the applications of this mechanical method are discussed briefly.