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Introduction: Slopes either occur naturally or are engineered by humans. An understanding of geology, hydrology, and soil properties is central to applying slope stability principles properly.
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Introduction: • Slopes either occur naturally or are engineered by humans. • An understanding of geology, hydrology, and soil properties is central to applying slope stability principles properly. • Analyses must be based upon a model that accurately represents site surface conditions, ground behavior, and applied loads. • Type of Analysis
Aim of slope • Assess the stability of slopes under short-term • Assess the possibility of slope failure / satbility • Understand failure mechanisms and the influence • Enable the redesign of failed slopes and the planning and design • The effect of seismic loadings on slopes • Safe and economic design of excavations, embankments, earth dams, landfills, and spoil heaps .
Introduction Geological discontinuities Effect of Water Geotechnical Properties of Material Mining Methods State of stress Geometry slope: Temperature Erosion Seismic effect Vegetation FACTORS AFFECTING SLOPE FAILURE
Introduction • Plane failure • Wedge Failure: • Toppling failure • Rockfalls • Rotational Failure TYPES OF ROCK SLOPE FAILURE
Planar Failure Analysis • Sliding analysis of a block • Plane failure analysis along a discontinuity • Water is filled in discontinuities • Tension crack present in the upper slope surface • Tension crack present in the slope surface • The tension crack is filled with water with upper slope angle • Effect of rock bolts • Wedge Failure Analysis • Analysis of wedge failure considering only frictional resistance • Analysis of wedge failure with cohesion and friction angle • Toppling Failure Analysis • Kinematics of block toppling failure • Limit equilibrium analysis for toppling failure • Stability analysis of flexural toppling Rock Slope Stability Analysis: Limit Equilibrium Method
Introduction • Stability analysis of slope • Stability analysis for Cohesionless Soil • Total Stress Analysis (Swedish slip circle method) • Ordinary slip circle method • Bishop’s Simplified Method of Slices • General Method of slices CIRCULAR FAILURE ANALYSIS
Introduction • Continuum modeling • Discontinuum Modeling • Hybrid approach • Important considerations • Continuum versus discontinuum models • Selecting appropriate zone size • Initial conditions • Boundary conditions • Water pressure • Excavation sequence • Important failure indicators in slope analysis • Factor of Safety • Unbalanced Force • Gridpoint Velocities • Plastic Indicators • Displacement • Failure Surface SLOPE STABILITY ANALYSIS BY NUMERICAL MODELLING
Introduction • Common terms used in simulation of water • Important Geotechnical properties related to water • Permeability • Hydraulic Conductivity • Factor affecting soil permeability and hydraulic conductivity • Matrix suction • Consistency of soil • Pore Pressures • Infiltration • Rainfall Infiltration Model. • Simulation of water STABILITY ANALYSIS IN PRESENCE OF WATER
Introduction Types of seismic wave Dynamic Soil Properties Field Measurements of Dynamic Modulus Ground Motion Estimates Factors Affecting Ground Motion: Simulation of seismic effect Pseudo-static approach Wedge Method Method of Slices Inertia Slope Stability – Newmark Method SEISMIC ANALYSIS
Introduction • Removal And Repair • Excavation & repair • Catchment & Wire Netting • Grading & Serrating • Benching • Resloping and unloading • Lightweight Fill • Counterberms • Trimming • Shear Keys • Scaling • Drainage and Water Control • Surface Drainage • Subsurface Drainage SLOPE STABILIZATION
Stabilization Through Support • Steel reinforcement • Rock anchor • Rock Bolts • Rock Dowels • Soil Nailing • Piles • Geosynthetic Reinforcement • Retaining Walls • Gravity Walls • Cantilever Retaining Walls • Sheet Piling Retaining Walls • Anchored retaining wall • Gabions • Other Methods For Stabilization • Grouting and Shotcrete • Vegetation
Introduction • Slope failure mechanism • Types of Slope Movement • Initial response • Regressive and progressive movement • Long-term creep • Sub-Surface Monitoring Methods • Borehole probes • Time–domain reflectometry • Inclinometers • Extensometers SLOPE MONITORING: TECHNIQUES AND INSTRUMENTS
Measurement of water level and pressure • Standpipe Piezometer • Pneumatic Piezometer • Vibrating Wire Piezometer • Surface Monitoring Methods • Crack Monitors • Surveying • Photographic Image Analysis • Total Station • Global positioning system (GPS) • Acoustic emission technique • Laser image scanning system • Slope Stability Radar system • Synthetic aperture radar
Introduction • Slope Failure • Slumps • Rock Falls and Debris Falls • Rock and Debris Slides • Sediment Flows • Solifluction • Debris Flows • Mudflows • Creeps • Earthflows • Debris Avalanches • Historical landslides (wiki ) • Major factors affecting landslides landslides
Introduction • Method of Construction in lift section • Methods of Stability Calculation • Shear Strength of dump material • Particle shape, roundness and grain surface texture • Effect of moisture condition on shear strength • Factors Affecting Dump Stability • Dump Configuration • Foundation Conditions • Dump Material Properties • Dumping method • Dumping Rate • Seismicity and Dynamic Stability • Topography • Dump drainage Mine Waste Dump
Material properties and testing • Bulk Gradation • Plasticity of Fines • Index Properties and Classification • Hydraulic Conductivity • Consolidation • Strength • Mineralogy and Soil Chemistry • In Situ Density • Compaction
Failure Modes in tailing dams • Rotational Sliding • Foundation Failure • Overtopping • Erosion • Piping • Tailings Impoundment Design • Mill Location • Topography • Geology and Ground Water • Tailings impoundments • Tailings storage facilities • Methods for Tailings Disposal • Upstream Method • Downstream Method • Centerline Method Tailing Dam
Sensitivity Analysis Probabilistic Design Methods Reliability Analysis Sensitivity, probability and reliability analysis
General Slope Mass Rating (SMR) Chinese Slope Mass Rating System (CSMR) Rock slope rating (RSR) Slope stability rating (SSR) classification system Dump mass rating Classification systems in slope stability analysis
Artificial Neural Network Fuzzy Inference System Introduction of softcomputing approach in slope stability