SEEING THE INVISIBLE

摘要

ROCK TUNNELS ARE USED EXTENSIVELY for conveying water in industrial and municipal applications, such as hydro and nuclear power, water for drinking, sewage water, raw water supply to industrial plants, and other instances. Hydropower is a major application of this infrastructure: tunnels in hydropower plants are usually a few kilometres in length with some even being tens of kilometres long. Although such tunnels are constantly flooded, they still need monitoring and maintenance inspections at regular intervals. In addition to rock fallouts, sediment collection can also impede water flow and cause blockages. Besides blockages in waterways, tunnel instability can in addition affect soil stability on top of the tunnel and cause gullies, with the potential risk of damage to third-party property and life.