Rock slope pre-failure deformation database for improved transportation corridor risk management

• Published in: Landslides and Engineered Slopes. Experience, Theory and Practice Vol. 1; pp. 1211 - 1217
• Main Authors: Kromer, R.A., Hutchinson, D.J., Lato, M.J., Abellán, A.
• Format: Book Chapter
• Language: English
• Published: CRC Press 2016
• Edition: 1
• Subjects: Filtered Point Cloud; Magnitude Failures; Deformation Time Series; Volcanic Sandstone; Western Canada; Pre-failure Deformation; Joint Set Orientations; Rock Slope; Railway Corridor; Terrestrial Laser; Overburden; Point Cloud; Landslide Types; Exact Failure Time; TLS; Slope Stability Analysis; Aligned Point Clouds; Rock Slope Failure; Failing Rock Mass; Larger Failures; Data Treatment Methods; Freeze Thaw Cycles; Study Time Window; Maintenance Resources; Rockfall Events
• ISBN: 1138029882; 9781138029880
• DOI: 10.1201/9781315375007-137

Linear transportation corridors are often exposed to a variety of landslide types, including rockfall and rock slide failures. In western Canada, these failures create one of the highest hazards for safe railway operation. In this study we begin the construction of a database of pre-failure slope deformation based on TLS monitoring of high rockfall activity sites along a railway corridor in western Canada. At an initial study site, we observed the majority of the rockfall events were preceded by detectable pre-failure deformation; and that most of the failures occurred during periods dominated by freeze-thaw cycles. This database can be used to understand failure probabilities of detected deforming areas and thus help risk management by better allocating maintenance resources and to reduce exposure to rockfall events. This database will also provide clues to the relationships between magnitude of failure and pre-failure deformation duration and intensity. This chapter explores the construction of a database of pre-failure slope deformation based on terrestrial laser scanner monitoring of high rockfall activity sites along a railway corridor in western Canada. It observes the majority of the rockfall events were preceded by detectable pre-failure deformation; and that most of the failures occurred during periods dominated by freeze-thaw cycles. With modern 3D monitoring technologies, such as the TLS and with appropriate data treatment methods, the pre-failure deformation phase of a failing rock-mass can be identified. Two observations from the case study are important for risk management: smaller failures occur more often and have lower duration and intensity of pre-failure deformation compared to larger failures; and, already deforming areas are more likely to fail during the subsequent freeze-thaw cycles. The total duration and intensity of pre-failure deformation for each event was tabulated in a dynamic table with conditional formatting.