- Copyright © 2016, Environmental & Engineering Geoscience
The Grohovo landslide is located on the northeastern slope in the central Rječina river valley, and the river mouth is located in the center of Rijeka city, Croatia. It is the largest active landslide along the Croatian coast of the Adriatic Sea. This complex retrogressive landslide was induced by earthquake occurred in the Rijeka City at the end of 18th century and was reactivated in December 1996. The Grohovo landslide poses a natural hazard to Rijeka city and it is necessary to perform 3D slope stability assessment. Slope deposits in the Grohovo landslide are mainly a mixture of clayey silt that was formed by the weathered Paleogene flysch rock and the fragments of limestone originating from the cliffs on the top of the slope. The basal failure surface is located at the contact between the slope deposits and the flysch bedrock. Based on borehole data, geological mapping, and the reconstruction of geological cross sections through the slope, this study interpolates the three dimensional shape and position of the sliding surface using a modified inverse distance weighted interpolation method. The entire Grohovo landslide and twelve separate sliding blocks, which have the same three-dimensional sliding surface, are analyzed using a modified 3D slope stability analysis based on a simplified force-equilibrium scheme.