Terrestrial laser scanning (TLS) deformation monitoring of a high-fill embankment in the Arctic

ABSTRACT: The Inuvik-Tuktoyaktuk Highway (ITH) in Northwest Territories, Canada was built during winter on ice-rich continuous permafrost with no cuts in the ground to preserve the permafrost foundation. Several high-fill sections were required along the highway to meet vertical geometry specifications. Embankments in Arctic regions are susceptible to deformations due to thawing of the frozen fill material and permafrost foundation at the embankment toes. One high-fill section along ITH was reinforced with woven geotextiles to reduce slope movements. The reinforced section and an adjacent control section were instrumented to monitor slope movements. Terrestrial laser scanning (TLS) was conducted at the research site in August 2018 and June 2019. A real-time kinematic (RTK) survey system was used to measure ground control point (GCP) positions for georeferencing the TLS reconstructed point clouds. Embankment deformations were determined by point cloud comparison. TLS deformations were compared to instrumentation deformation data. This paper presents the methodology and results of the TLS deformation monitoring. Limitations of the technologies are discussed and recommendations for deformation monitoring using TLS are provided.