Measurement of Landslide Displacement by object extration with ground based Portable Lased Scanner
2. OBJECTIVES
In this study, a method for 3D object extraction was developed. The location and attitude of
extracted objects can be compared accurately in time series. Developed method was applied to
monitor landslide displacement.
3. TEST AREA
In Shikoku, Japan, four big active faults exist. Many landslide is occurred along the active
fault. Now, landslide prevention areas exist over 1,500 places in Shikoku, Japan. In this study,
test area was selected Chouja landslide, Shikoku, Japan. In Chouja, width of landslide is about
200m, length is about 900m and average slope is about 15 degrees. It is one of the biggest
landslides in Japan. As Observation site, shore-protection blocks was selected (Figure 1).
Because they are located in the end of landslide area where has big movement.
Figure 1: Observation area
4. LASER SCANNER
In this study, ground based portable Laser Scanner (RIEGL Japan. Ltd.)
was used. It is a kind of electro-optical distance meter without prism.
Maximum measurement range is 350m. Accuracy is about 0.025m in
standard deviation. Measurement principle was the same as a Total Station.
Table 1 showed specification of Laser Scanner. Figure 2 showed image of
Laser Scanner.
Table 1: Specification of laser scanner
Figure 2: LMZ-210
