Dot study of lidar geotechnical applications in eight states

Terrestrial LIDAR is a new technology that produces "point clouds" of reflection points that represent a scanned 3D surface. This data can be processed to determine important geotechnical information, including discontinuity attributes (orientation, roughness, spacing, length, block size, persistence, etc.), detailed 3D surface topography for cross sections and rock fall trajectory studies, and change detection [1]. Eight states are collaborating in a Department of Transportation (DOT) pooled fund study to explore the use of terrestrial LIDAR for collecting and processing point cloud data for geotechnical applications [2]. These states are AZ, CA, CO, NH, NY, PA, TN and TX. The project includes selection of a field site in each state and the scanning of this site, analysis of data from the site, a series of training workshops to review the results and instruct DOT personnel on the use of LIDAR and point cloud processing software, and a final report with detailed results and suggestions for utilizing LIDAR for highway geotechnical applications. This paper will present preliminary results from the eight states that look at a variety of LIDAR applications including slope stability, rock fall simulation, change detection, and rock mass characterization. Based on this study and the final report that will be issued, all states will be able to determine if LIDAR can be an effective alternative to traditional methods of gathering and analyzing geotechnical data.