Combining temporal 3D remote sensing data with spatial rockfall
simulations for improved understanding of hazardous slopes within
rail corridors
Abstract. Remote sensing techniques can be used to gain a more detailed understanding of hazardous rock slopes along railway corridors that would otherwise be inaccessible. Multiple datasets can be used to identify changes over time and create an inventory of rockfall events including frequency-magnitude relationships for rockfalls sourced on the slope. This study presents a method for using the remotely sensed data to develop inputs to rockfall simulations, which can be used to determine the likelihood of a rockfall impacting the railway tracks given it’s source zone location and volume. The results of the simulations can be related to the rockfall inventory to develop modified frequency-magnitude curves presenting a more realistic estimate of the hazard. These methods were developed using the RockyFor3D software and LiDAR and photogrammetry data collected over several years at the White Canyon, British Columbia, Canada, where the CN Rail main line runs along the base of the slope. Rockfalls sourced closer to the tracks were more likely to be deposited on the track or in the ditch, and of these, rockfalls between 0.1 and 10 m3 were the most likely to be deposited. Smaller blocks did not travel far enough to reach the bottom of the slope and larger blocks were deposited past the tracks. Applying the results of the simulations to a database of over 2000 rockfall events, a modified frequency-magnitude can be created, allowing the frequency of rock falls deposited on the railway tracks or in ditches to be determined. Suggestions are made for future development of the methods including refinement of input parameters and extension to other modelling packages.