COMPARISON BETWEEN DIFFERENT METHODS OF ROCK SLOPE ANALYSIS AND RISK ASSESSMENT

Abstract

Instability in rock slopes is a very common phenomenon due to complex formations of different geological structures within the rock masses. These instabilities pose a significant threat to civil engineering projects such as the cutting of rock slopes for road or railway construction, open pit mining etc. Engineers have developed different techniques over the centuries to determine the level of stability of slopes in a given rock mass. This project aims to evaluate and compare various techniques for analyzing rock slopes and assessing associated risks. This research involves a comprehensive assessment of geological and geotechnical data to classify rock masses using the Rock Mass Rating (RMR) and Geological Strength Index (GSI) systems. These classifications provide a foundation for understanding the rock mass behavior and stability. The classification of rock mass further provides the basis for determination of strength parameters using different criterion such as Hoek & Browne, Mohr Coulomb and Barton-Bandis criterion. Subsequently, the project determines the potential modes of failure through kinematic analysis, which considers the geometric relationships between the rock structures and the slope face. This analysis identifies the likelihood of different failure types such as planar, wedge, and toppling failures. To quantify the stability of the slopes, the project employs limit equilibrium analysis to calculate the Factor of Safety (FoS). This method evaluates the balance of driving and resisting forces on potential failure surfaces, offering a measure of slope stability. By incorporating factors for seismic accelerations and water pressure the limit equilibrium equations can be modified to quantify the safety factor against flooding and earthquakes. By comparing these methods, the research aims to highlight the strengths and limitations of each approach in various geological contexts. The outcomes are expected to provide valuable insights for selecting appropriate analysis techniques for rock slope stability and risk assessment, ultimately contributing to safer and more effective slope management practices.