Abstract
To contribute the productivity growth during mountain tunnel construction, development of the technologies related to laborsaving and safety management using ICT is necessary. We developed a measurement and visualization system that combines 3D scanning with projection mapping technology. The system can quickly provide result of the scanning data of the surface of tunnel excavation and some equipped framework in the mountain tunnel to the workers and administrators. The usage of the system is divided into two parts for (1) management of excavation surface shape such as crown, side wall, and invert of tunnel, and (2) management of installation of the joint steel bars used for lining concrete. This paper represents the specification of the system, results of the field test, and effectiveness and difficulty of the usage.
In the field of mountain tunnels construction, the development of technologies related to laborsaving and safety management using ICT is necessary to contribute the productivity growth. We developed a measurement and visualization system that combines 3D scanning with projection mapping technology. The system can quickly provide result of the scanning data of the tunnel excavation surface and some equipped framework in the mountain tunnel to workers and administrators. These systems allow easy understanding of the measured data by projecting the image onto complex surfaces such as the crown, side wall, and invert of tunnel. We report the outline of developed two systems and the results of field test.
In mountain tunnels, the excavation shape of crown, side wall, and bottom of the tunnel, is made sure to satisfy the section design of the tunnel. The effect of reducing extra excavated muck, shotcrete and lining concrete is expected by these validations. Fig. 1 shows an example of conventional measurement method of invert excavation using string level and scale such as marked rod. A few workers enter the excavation site to make sure the shape of the excavation area. There are greater risk of injury and accident. In order to improve safety, Metoki had developed the system that the laser beam is projected onto the tunnel face to show the drilling point (Metoki, 1991). We developed a measurement and visualization system that the projected image shows the difference between the designed and actual shape of the excavation surface directly. The field test used this system was conducted during invert excavation of an actual mountain tunnel to validate the visibility and accuracy of the projected image.
