Numerical Modelling of Slope Instability

Abstract

This article is dealing with stability of the highway cut in Eastern Slovakia. The cut is situated in rock environment of the Carpathian flysch, which in area of the cut mostly consists of shale with different degree of weathering. The cut is supported by an anchored pile wall. Rock environment is changing from the surface to the depth from alluvium clays, sands and completely weathered shale to fresh shale. The potential slip surface was investigated after evaluation of data from geotechnical monitoring, so stability of the pile wall has to be analyzed. Finite element analysis was done and two material models were compared to results of geotechnical monitoring. Deformation analysis and the safety factor are discussed. Two models were compared in these terms: Mohr - Coulomb material model and jointed rock material model. These models are introduced because of shale anisotropy and simplification of behavior model via jointed rock model. Jointed rock model was introduced as an anisotropic model and required geotechnical parameters for calculations are discussed in comparison with the Mohr – Coulomb material model. Anisotropic behavior of shale will be discussed and analyzed. Short recommendations for the use of these models are presented in the paper.This article is dealing with stability of the highway cut in Eastern Slovakia. The cut is situated in rock environment of the Carpathian flysch, which in area of the cut mostly consists of shale with different degree of weathering. The cut is supported by an anchored pile wall. Rock environment is changing from the surface to the depth from alluvium clays, sands and completely weathered shale to fresh shale. The potential slip surface was investigated after evaluation of data from geotechnical monitoring, so stability of the pile wall has to be analyzed. Finite element analysis was done and two material models were compared to results of geotechnical monitoring. Deformation analysis and the safety factor are discussed. Two models were compared in these terms: Mohr - Coulomb material model and jointed rock material model. These models are introduced because of shale anisotropy and simplification of behavior model via jointed rock model. Jointed rock model was introduced as an anisotropic model and required geotechnical parameters for calculations are discussed in comparison with the Mohr – Coulomb material model. Anisotropic behavior of shale will be discussed and analyzed. Short recommendations for the use of these models are presented in the paper.