68th Canadian Geotechnical Conference and 7th Canadian Permafrost Conference

3D DATA COLLECTION FOR RAPID ROCK FALL RESPONSE SITUATIONS

Session: Landslides and Slope Stability IV / Mouvements de terrain et stabilité des pentes IV

Matt Lato, BGC Engineering Inc. (Canada)
Dave Gauthier, BGC Engineering (Canada)
Pete Quinn, BGC Engineering Inc. (Canada)
Jean Hutchinson, Queen's University (Canada)
Ryan Kromer, Queen's University (Canada)
Tom Edwards, CN Railway (Canada)
Jose Riopel, QNS&L Railway (IOC) (Canada)

Linear infrastructure corridors in rugged terrain are typically vulnerable to rockfall and rockslide type natural hazards. Once a hazardous event has occurred that warrants investigation in relation to the safety of the site it is critical to collect detailed information quickly. The Railway Ground Hazard Research Program has invested in the development of remote sensing techniques that can be deployed in a rapid response scenario. Oblique Helicopter Photogrammetry (OHP) is a technique that enables the generation of 3-dimensional (3D) point cloud data from photos using Structure from Motion (SfM) photogrammetry. This paper discusses two case studies in which the operator of a single track railway line experienced a rockslide event that required an immediate engineering response. The first case study is located along a CN railway line 150 km northeast of Vancouver, BC where a rockslide activated a slide detector fence. The second site is located along a QNS&L railway line 20 km north of Sept-Iles, QC where a rockslide covered the tracks and forced the temporary closure of the railway. An immediate response was undertaken by both railways. In both instances the time between data collection and initial model development was less than 24 hours.