Regional 3D Stability Analyses of the Egkremnoi Coastline and Comparison with Landslides Caused by the 2015 Lefkada Earthquake
Publication: IFCEE 2021
ABSTRACT
Regional three-dimensional (3D) forward modeling stability analyses are presented for the Egkremnoi coastline of Lefkada Island in Greece. The pre-earthquake 5-m resolution DEM of the region was used as input for the regional 3D model and the modeling results were evaluated for five large landslides that occurred in the area during a Mw 6.5 earthquake that occurred in 2015. The area ratio and the overlap area ratio were defined to quantitatively assess the geospatial “match” between predicted and mapped landslides. Parametric analyses using variable material strength and DEM resolution were subsequently conducted to assess the influence of the input on the estimates of factor of safety, geometry, and location for the predicted most critical landslide. For the cases studied here, the assumed material strength has a greater influence on the factor of safety compared with DEM resolution. However, we find that the DEM resolution has a more pronounced influence on the location and size of predicted landslides.
Get full access to this article
View all available purchase options and get full access to this chapter.
REFERENCES
Bentley Systems. (2020). SOILVISION Edition V10. Exton, Pennsylvania, United States.
Ganas, A., Elias, P., Bozionelos, G., Papathanassiou, G., Avallone, A., Papastergios, A., Valkaniotis, S., Parcharidis, I., and Briole, P. (2016). Coseismic deformation, field observations and seismic fault of the 17 November 2015 M= 6.5, Lefkada Island, Greece earthquake. Tectonophysics, 687, 210-222.
Grendas, N., Marinos, V., Papathanassiou, G., Ganas, A., and Valkaniotis, S. (2018). Engineering geological mapping of earthquake-induced landslides in South Lefkada Island, Greece: evaluation of the type and characteristics of the slope failures. Environmental Earth Sciences, 77(12), 425.
Kallimogiannis, V., Saroglou, C., Zekkos, D., and Manousakis, J. (2019) 2D and 3D Back-analysis of a landslide in Egremnoi caused by the November 17 2015 Lefkada earthquake. In 2nd International Conference on Natural Hazards & Infrastructure, Chania, Greece.
Spencer, E. (1967). A method of analysis of the stability of embankments assuming parallel inter-slice forces. Géotechnique, 17(1), 11-26.
SoilVision Systems Ltd. (2019). SVSLOPE Theory Manual. Saskatoon, Saskatchewan, Canada.
U.S. Geological Survey. (2015). Advanced National Seismic System (ANSS), ShakeMap, Global Region, Maps of ground shaking and intensity for event us10003ywp, GREECE. https://earthquake.usgs.gov/earthquakes/eventpage/us10003ywp/shakemap/pga?source=us&code=us10003ywp.
Valkaniotis, S., Papathanassiou, G., and Ganas, A. (2018). Mapping an earthquake-induced landslide based on UAV imagery; case study of the 2015 Okeanos landslide, Lefkada, Greece. Engineering geology, 245, 141-152.
Zekkos, D., and Clark, M. (2020). Characterization of landslides and rock mass strength leveraging the 2015 Mw 6.5 Lefkada Earthquake in Greece. U.S. Geology Survey. National Earthquake Hazards Reduction Program, Award Number G17AP00088.
Zekkos, D., Clark, M., Cowell, K., Medwedeff, W., Manousakis, J., Saroglou, H., and Tsiambaos, G. Satellite and UAV-enabled mapping of landslides caused by the November 17th 2015 Mw 6.5 Lefkada earthquake, in: Proc. 19th Int. Conference on Soil Mechanics and Geotechnical Engineering, 17–22 September 2017, Seoul, 2017.
Zekkos, D., Greenwood, W., Lynch, J., Manousakis, J., Athanasopoulos-Zekkos, A., Clark, M., and Saroglou, C. (2018). Lessons learned from the application of UAV-enabled structure-from-motion photogrammetry in geotechnical engineering. International Journal of Geoengineering Case Histories, 4, 254-274.
Information & Authors
Information
Published In
IFCEE 2021
Pages: 130 - 138
Copyright
© 2021 American Society of Civil Engineers.
History
Published online: May 6, 2021
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.