Evaluation of UAV LiDAR Survey for Detecting Soft Ground Settlement at Construction Site in Coastal Area of Korea

Rapid and efficient 3D spatial-information-collecting technology has recently become necessary in construction work. In particular, the use of light detection and ranging (LiDAR) techniques to collect and model 3D location information using a laser scanner connected to an unmanned aerial vehicle (UAV) or aircraft is growing. When civil engineering work is performed on soft ground, it results in engineering issues such as long-term settlement and localized structural damage. However, research on LiDAR survey of soft ground is limited. Therefore, a construction site in a coastal area, a container terminal (Stages 2–6) in Busan New Port, was selected as the target of this study to validate the efficacy of using UAV LiDAR survey to assess the settlement of soft ground. The performance of the UAV LiDAR survey for soft ground settlement calculation was evaluated by comparing and analyzing the settlement calculation performance using a digital elevation model (DEM) grid time-series analysis with the performance of settlement measurement using a measuring instrument. As a result of this study, the method of calculating settlement using UAV LiDAR and DEM applied in this study is judged to satisfy the field survey regulations for calculating soft ground settlement.