Rescue effort at site of slope collapse caused by the 2004 Niigata Chuetsu earthquake and firefighters observing the cliff aboveIn Japan, some 50 people on average lose their lives each year in landslides and other types of slope-related disasters, which are a major form of natural disaster. The prevention of secondary disasters should be the major focus when conducting rescue efforts in areas around landslide disaster sites. At present, the visual monitoring of slopes by the eye is the main method used, but this is problematic in many ways due to the limited area of visibility at night, declining attentiveness of human monitors over long periods, and difficulty in detecting gradual changes, for example.

In response, we are developing a technique for remotely detecting slope deformations using a laser scanner instead of visual monitoring. This technique will allow for the rapid monitoring of slope abnormalities over a wide area from a safe location. Through our research thus far, we have become able to detect where abnormalities (deformation) exist on a slope and whether the deformation in question is progressing. We are now conducting research on a method to forecast when a landslide is likely to occur, based on the detected deformation. Also, we plan on collecting case studies of rescue efforts during landslide disasters to do research on methods of estimating where missing people are likely to be found.

Slope monitoring system using a laser scanner.This system remotely monitors slope deformation in real time

Slope deformation observed using a laser scanner in collapse test on a natural slope