The movement detection on the landslide surface by using Terrestrial Laser Scanning

Abstract

The landslide is a natural process that continuously affecting many tropical countries, especially in the monsoon season. For the past 25 years, many rainfall-induced landslides have occurred throughout our country that strikes the citizens, especially near the hillside areas. Due to complicated regional geological structures and high rainfall intensities, landslide disasters happen frequently in Malaysia. The study of a landside site involves many aspects of data collection and data analysis activities. Typically, a variety of conventional and modern methods had been used to assess the displacement of landslide such as precise levelling, total station and Close Range Photogrammetry (CRP), Real Time Kinematic Global Positioning System (RTK-GPS), Reflectorless Total Station, Satellite Remote Sensing Imagery, and Airborne Laser Scanning (eg. Lidar. Each of these methods posed their own advantages and limitations. Since slopes evolve continuously as a result of natural processes, better and faster tools related to generating more realistic 3-D Digital Terrain Model (DTM) representation of the landslide sites are desired. Therefore, Terrestrial Laser Scanning (TLS) has become as an ideal tool to serve such a purpose since it offers very high resolution of spatial sampling in 3D measurement and also without contact with the hazardous area make it as a helpful observation in landslide assessment. This study therefore is being conducted to assess the potential of terrestrial laser scanner to monitor the change of the landslide surface Ulu Behrang, Perak, Malaysia. High-density point cloud measurement, laser-scanner Leica ScanStation2 has been used to produce an accurate representation of these complex surfaces. The overall results are presented and discussed.