Using LiDAR to measure subsurface movement of slow-moving landslides and study the interaction between the soil and LiDAR scanning targets

Terrestrial Laser Scanning (TLS) technology has been used for predicting and researching geological hazards for two decades. This research focuses on using LiDAR (Light Detection And Ranging) to measure the slow-moving displacement of both surface and subsurface soil of landslides. Two kinds of computer simulation software, FLAC3D® and PFC3D® were used to simulate the landslide process to compare with the LiDAR scanning results. The primary contributions from this research are as follows: 1. Several error tests were done to prove that the three-dimensional LiDAR scanner used in this research can precisely obtain the three-dimensional position, the displacement and the rotational angle of artificial scanning targets. 2. Two kinds of special scanning targets were used for the laser scanner to measure the displacement of surface and subsurface of soil. 3. A series of shear box tests and computer simulation programs were designed to study the interaction between the target rod and the soil so as to prove if the target rods can accurately reflect the subsurface movement of the soil. 4. A large-scale bench model test was designed to prove the applicability of the new LiDAR monitoring method. This research is innovative and important because it proves the designed scanning targets verifies the function of the LiDAR, and several experiments were used to prove the precision and principle of this new monitor method --Abstract, page iii