Grant: Alliance Grants

Landslides are a significant risk in Canada, especially in Southern Quebec, with about 108 historical retrogressive landslide cases in sensitive clays. Erosion and earthquakes trigger numerous landslides, emphasizing the region's high vulnerability. This profoundly affects various industries, including Hydro-Quebec, and municipalities like the City of Saguenay. The project aims to enhance slope stability tools for accurate prediction of retrogressive landslides under diverse loading and environmental conditions. It also seeks to develop a 3D slope stability GIS framework using 3D geological modeling. Firstly, the project focuses on determining the static and dynamic characteristics of sensitive clay in the Laflamme sea region. Subsequently, a 3D model of the subsoil in Saguenay Lac Saint-Jean will be developed. Seismic shaking effects will be assessed through shear wave velocity (Vs) in surface deposits, utilizing geophysical and geotechnical tests conducted as part of the project, and available data for the region. An enhanced slope stability tools will be developed, integrating both analytical and numerical methods to predict landslides in LaFlamme sea deposits, with a particular focus on retrogressive landslides. These modifications are crucial as they will provide more accurate predictions for both the run-out and retrogressive distances, which are key parameters for assessing the risk associated with this phenomenon. Finally, developed tools will be implemented in a GIS, along with a 3D geological model, constituting comprehensive landslide susceptivity map for this region considering various triggering factors of landslides such as erosion, rainfall and earthquake.