Figure 3.
The image captures the interior of a large cylindrical tunnel from a perspective that showcases its smooth, metallic walls. In the foreground, several construction workers, dressed in safety gear, gather near an elevated platform composed of scaffolding and equipment, suggesting ongoing work. The setting is well-lit, illuminating the curved structure of the tunnel and the industrial environment, characterised by pipes and electrical connections. The width of the tunnel emphasizes its scale, creating a sense of depth leading towards the centre where the workers are located. Additional details like the polished surface of the walls and various construction materials enhance the scene's context in a construction or engineering project.Main tunnel primary segmental and secondary cast-in-situ secondary linings