Handbook on Tunnels and Underground Works. Volume 1, Concept - Basic Principles of Design.

Cover
Half Title
Title Page
Copyright Page
Table of Contents
Preface
Foreword 1
Foreword 2
About the editors
Contributors
1 Introduction
	1.1 Historical overview
	1.2 Design approaches
	1.3 Geometry of tunnels, layout and alignment
	1.4 Management of the design process
	Authorship contribution statement
	References
2 Risk management in tunnelling
	2.1 Introduction
	2.2 Planning/feasibility study
		2.2.1 Definition of tendering strategies
		2.2.2 Constraints identification
		2.2.3 Risk assessment/evaluation/allocation
		2.2.4 Definition of risk acceptability criteria
		2.2.5 Choice of mitigation measures
	2.3 Engineering
		2.3.1 Definition of key performance indicators and related threshold
		2.3.2 Design of mitigation measures
		2.3.3 Design during excavation survey and monitoring
		2.3.4 Residual risk assessment/evaluation
		2.3.5 Forecasting of potential countermeasures
		2.3.6 Preliminary maintenance plan and long-term monitoring design
	2.4 Construction
		2.4.1 Implementation of mitigation measures
		2.4.2 During-construction survey and monitoring
		2.4.3 Residual risk assessment/evaluation
		2.4.4 Design/implementation of possible countermeasures and update of long-term monitoring
	Authorship contribution statement
	References
3 Input data: geology and hydrogeology
	3.1 Introduction
	3.2 Engineering geology for tunnelling and underground works
	3.3 The geological model: features and hazards
		3.3.1 The identification of the different typologies of media
		3.3.2 The geomorphological issues
		3.3.3 Tectonic and structural issues
		3.3.4 Geological issues
		3.3.5 Hydrogeological issues
			3.3.5.1 The groundwater as a resource
	3.4 Geological and hydrogeological investigations
	3.5 Natural state of stress and its assessment
	3.6 Geothermal gradient
	3.7 Seismicity
	3.8 Swelling, squeezing and rock burst
		3.8.1 Swelling
		3.8.2 Squeezing
		3.8.3 Rock burst
	3.9 Aggressive waters, gas, radon, and asbestos
		3.9.1 Aggressive waters
		3.9.2 Gas
		3.9.3 Radon
		3.9.4 Asbestos
		3.9.5 Karst
	3.10 Summary
	Authorship contribution statement
	References
4 Input data: geotechnics
	4.1 Introduction
	4.2 Fundamental concepts for the hydro-mechanical characterization of geotechnical materials
		4.2.1 Elasticity
		4.2.2 Plasticity
		4.2.3 Brittleness
		4.2.4 Viscosity
		4.2.5 Anisotropy
		4.2.6 Effective stresses
		4.2.7 Hydraulic conductivity
		4.2.8 Drained and undrained conditions
	4.3 Mechanical properties of soil and intact rock elements
		4.3.1 Strength
		4.3.2 Stiffness
	4.4 Rock mass and rock discontinuities
		4.4.1 Definitions
		4.4.2 Description of discontinuity systems
		4.4.3 Shear strength of discontinuities
		4.4.4 Rock mass classification systems
	4.5 Mechanical properties of the rock masses
		4.5.1 General framework
		4.5.2 Rock mass strength
		4.5.3 Rock mass stiffness
	4.6 In situ stress conditions
	4.7 Special issues in geotechnical characterization for tunnelling
		4.7.1 Soil behaviour in shallow tunnelling
		4.7.2 Swelling and squeezing conditions
		4.7.3 Rock properties for spalling prediction
		4.7.4 Importance of the post-peak behaviour for the rock mass around deep tunnels
		4.7.5 Problems in the characterization of fault rocks, tectonized rocks and fault filling materials
		4.7.6 Identification and hydraulic characterization of water-bearing structure
	4.8 Planning and execution of in situ surveys and investigations
		4.8.1 Site investigations
		4.8.2 Survey
		4.8.3 Exploratory boreholes and sampling
		4.8.4 In situ testing and monitoring
	4.9 Laboratory tests
		4.9.1 Uniaxial compression tests
		4.9.2 Triaxial tests
		4.9.3 Tensile tests
		4.9.4 Shear box tests
		4.9.5 One-dimensional consolidation and swelling tests
		4.9.6 Cyclic and dynamic mechanical tests
		4.9.7 Small-scale prototype tests – extrusion tests
		4.9.8 Index tests for cutting tools optimization
		4.9.9 Clogging potential in TBM tunnelling
	4.10 In situ tests
		4.10.1 Soil mechanics tests
		4.10.2 Rock mechanics tests
		4.10.3 Geophysical testing methods
		4.10.4 Tests for the determination of hydraulic parameters
	4.11 The geotechnical model
		4.11.1 Purpose
		4.11.2 Content
		4.11.3 Representation
		4.11.4 Design stage
		4.11.5 Construction stage
	Authorship contribution statement
	References
5 Environmental aspects
	5.1 Introduction
	5.2 Portal tunnel design
	5.3 Interference between the tunnel and the underground water
	5.4 Excavated muck management
		5.4.1 Management of soil excavated by EPB-TBM
	5.5 Management of asbestos-bearing rock masses
		5.5.1 Mitigation measures for the management of excavation material containing asbestos
		5.5.2 Mitigation measures at the storage sites (intermediate or final)
	5.6 Life cycle assessment and carbon footprint of a tunnel construction
	Acknowledgements
	Authorship contribution statement
	References
6 Occupational Health and Safety aspects
	6.1 Introduction
	6.2 Occupational safety and health key points
		6.2.1 OS&H RAM principles
		6.2.2 Use of the proposed approach
	6.3 OS&H hazard identification
		6.3.1 Context-related hazards
		6.3.2 Work-related hazards
	6.4 Some insights
		6.4.1 Emergency and rescue design criteria
			6.4.1.1 Safety concepts
			6.4.1.2 Survival shelters
			6.4.1.3 Escaping from underground
		6.4.2 Ventilation design criteria
			6.4.2.1 Goal and design principle of the ventilation systems
	Acknowledgments
	Authorship contribution statement
	References
7 Preliminary risk assessment
	7.1 Introduction
	7.2 Uncertainties and risks
	7.3 The risk management plan
	7.4 Underground works, geology, hydrogeology and geotechnics
	7.5 Uncertainties and risks
	7.6 Preliminary assessment of geological and geotechnical sources of uncertainties and risks
	7.7 Preliminary assessment of other sources of uncertainties and risks
	7.8 A special focus on rock burst and squeezing hazards
		7.8.1 Rock burst
			7.8.1.1 Spalling susceptibility: shear vs spalling (brittle) failure
			7.8.1.2 Strain burst Potential (SBP) and Strainburst Severity (SBS)
			7.8.1.3 Rock burst damage severity
			7.8.1.4 Damage Index (DI) and Depth of Failure (DOF)
			7.8.1.5 Dynamic Rock burst Hazard
		7.8.2 Squeezing
		7.8.3 Illustrative approaches for a preliminary analysis of rock burst- and squeezing-related risks
			7.8.3.1 Example I for a deep alpine tunnel
			7.8.3.2 Example II for a deep Andean tunnel
	Authorship contribution statement
	References
8 Construction methods
	8.1 Introduction
	8.2 Excavation methods
		8.2.1 Conventional method
			8.2.1.1 Drill and blast
			8.2.1.2 Drill and split
			8.2.1.3 Roadheader
			8.2.1.4 High-energy impact hammer
			8.2.1.5 Excavator with shovels or with ripper tooth
		8.2.2 Full-face mechanized tunnelling method
	8.3 Support technologies
		8.3.1 First-phase lining
		8.3.2 Final lining
	8.4 Most frequently used auxiliary methods
	Acknowledgements
	Authorship contribution statement
	References
9 Computational methods
	9.1 Modelling approaches and calculation methods
		9.1.1 Introduction
		9.1.2 Analytical solutions
		9.1.3 Integrated/derived solutions
		9.1.4 Solutions for stability analyses
			9.1.4.1 Limit equilibrium method
			9.1.4.2 Limit analysis
		9.1.5 Numerical methods
			9.1.5.1 FEM
			9.1.5.2 FDM
			9.1.5.3 DEM
			9.1.5.4 Safety factor numerical estimation
	9.2 Analysis of the excavation phase
		9.2.1 Hydro-mechanical coupling
		9.2.2 The excavation process as an evolving geometry problem
			9.2.2.1 Three-dimensional analyses
			9.2.2.2 Axisymmetric approach
			9.2.2.3 2D fixed geometry analyses
		9.2.3 Modelling of support and reinforcement systems
		9.2.4 Simplified approaches for estimating the mechanical response of tunnel face in soils
			9.2.4.1 Shallow tunnels
			9.2.4.2 Deep tunnels
		9.2.5 Simplified approaches for the analysis of the tunnel cross section
			9.2.5.1 Shallow tunnels
			9.2.5.2 Deep tunnels
		9.2.6 Stability of rock wedges
	9.3 Interferences
		9.3.1 Tunnel water inflow and influence of tunnelling on groundwater regime
		9.3.2 Induced subsidence and interaction with pre-existing underground and surface structures
			9.3.2.1 SSI uncoupled approaches
			9.3.2.2 SSI coupled approaches
			9.3.2.3 Inclined strata
		9.3.3 Vibrations induced by drill and blast tunnel excavation
	9.4 Long-term tunnel performances
		9.4.1 HM coupled processes
		9.4.2 HTCM coupled processes
		9.4.3 Full SSI dynamic analyses for tunnels under seismic actions
		9.4.4 Tunnel–landslide interaction
		9.4.5 Thermo-mechanical coupling
	Authorship contribution statement
	References
10 Assessment of excavation-related hazards and design of mitigation measures
	10.1 Introduction
		10.1.1 Codes and partial factors
	10.2 Excavation phase
		10.2.1 Conventional tunnelling
			10.2.1.1 Sequential excavation
			10.2.1.2 Pre-support by means of forepoling techniques
			10.2.1.3 Pre-confinement by means of face reinforcements
			10.2.1.4 Dewatering and drainage
			10.2.1.5 Design of pre-improvement techniques for tunnelling
			10.2.1.6 First-phase and final support design
		10.2.2 Mechanized tunnelling
			10.2.2.1 The design of the face support for ‘earth pressure’ (EPB) and ‘slurry’ shields (SS)
			10.2.2.2 TBM jamming
			10.2.2.3 Design of precast segments
		10.2.3 Design of waterproofing
			10.2.3.1 Design bases
			10.2.3.2 Waterproofing approaches
			10.2.3.3 Waterproofing technologies
		10.2.4 Interferences
			10.2.4.1 Displacement field induced by tunnel excavation
			10.2.4.2 Simplified assessment of the effect on buildings of tunnelling-induced displacements
	10.3 Application of observational method in tunnelling
	10.4 Long-term tunnel performances
		10.4.1 Interferences between landslides and tunnels
		10.4.2 Seismic loads
			10.4.2.1 Ground Shaking
			10.4.2.2 Ground failure
		10.4.3 Design of lining against fire
			10.4.3.1 Structural requirements
			10.4.3.2 Material behaviour relevant for fire design
			10.4.3.3 Spalling
	Authorship contribution statement
	References
11 Monitoring during construction
	11.1 Introduction
	11.2 Relevant physical quantities and measurement techniques
		11.2.1 Tunnel monitoring
			11.2.1.1 Conventional tunnelling
			11.2.1.2 Mechanized tunnelling
		11.2.2 Surface monitoring
	11.3 Calculations for monitoring purposes – warning thresholds
	11.4 Concluding remarks
	Authorship contribution statement
	References
12 Maintenance and refurbishment of existing tunnels
	12.1 Introduction
	12.2 Degradation phenomena and damages
	12.3 Inspections and monitoring
		12.3.1 Inspections
		12.3.2 Monitoring
	12.4 Maintenance activities, repair works and protective measures
	12.5 Refurbishment works
		12.5.1 Methods
			12.5.1.1 Water control
			12.5.1.2 Structural improvement
		12.5.2 Design
	12.6 Concluding remarks
	Authorship contribution statement
	References
13 Project acceptance strategy
	13.1 Introduction
	13.2 The social and communication context of the 20th and 21st centuries
		13.2.1 The stakeholders
		13.2.2 The path of creation of awareness and/or cooperation
		13.2.3 The strategies, the ‘significant’ contents and the communication tools
	13.3 Conclusions
	Acknowledgements
	References
Glossary
Index