As-built modeling and visual simulation of tunnels using real-time TBM positioning data

To fulfill the needs of construction quality, progress control and sustainable development of the underground space, it is desirable to collect and visualize as-built tunnel information in real time. In the current practice, the as-built model of a tunnel is produced either by using advanced technologies like 3D laser scanning after construction ends, or by employing specialist tunnel surveyors to directly measure the invert positions. However, limitations of commonly applied as-built tunnel survey methods are identified in terms of accuracy, cost, or modeling speed. In this paper, we propose a new approach to enabling as-built modeling and visualization of tunnels based on real-time TBM tracking and positioning data. With a tunnel alignment automation control system being implemented, the TBM is turned into a “sensor” to map out as-build information in real time, without incurring extra labor cost or survey equipment. The proposed approach was field-tested and preliminary findings are discussed.