CE 006 UNDERGROUND STRUCTURES SYLLABUS:
1. Introduction to tunnelling:
Fundamental definitions, tunnelling art and engineering, historical development
2. Geological aspects of tunnelling:
Geological investigation, evaluation and appreciation, importance of geological
knowledge, aim of geological investigation, principal elements of exploration
programme, Influence of geological conditions on design and construction of tunnels
3. The Geological Environment:
Igneous, sedimentary and metamorphic rocks, Rock alteration, rock mass deformation
by folding action, faults: characteristics and influence on tunnelling, joints and their
relevance to tunnelling, groundwater aspects, squeezing and swelling ground
conditions, gases in rocks. rock temperatures, sloping ground surface conditions,
tunnelling in soft ground, classification of soft ground tunnelling conditions, rockburst
phenomena in tunnels.
4. Tunnelling methods: Soft ground conditions,
Shield Tunnels, Advantages of shield tunnelling, Conventional Tunnelling Shields,
Open Shield, Closed and Half Shields, Special Features of Shield Tunnelling,
excavation, Shield control, Settlement, Pipe Jacking, Special Shield Tunnelling
Methods, The D.K. Shield, Slime shields, Earth Pressure Balance Shield, Slurry-shield
tunnelling,
5. Tunnelling methods: rock conditions using drill and blast
Influence of rock strength on excavation, influence of tunnel size, summary of drilling
and blasting method of tunnel excavation drilling blasting debris clearance, ground
support drilling and blasting: basic operations, tunnel excavation using explosives,
blasting cuts, minimising ground vibrations, blasting with non-electric initiation,
improved blasting efficiency, rock drillability factors, percussive drilling, mechanism
of rock breakage, smooth profile blasting, computer-aided drilling, tunnelling progress
with drill and blast excavation
6. Tunnelling methods: rock conditions using roadheader machine excavation
Roadheaders: development and application, roadheaders: tunnelling experience and
practice roadheaders: power and weight, cutting principle of roadheaders: ripping
versus milling, high-pressure water jet assisted cutting, cutter picks, large radial picks,
forward attack picks, roadheader cutting ability, improved control of roadheaders,
roadheaders flexibility and adaptability to tunnelling conditions
7. Adverse ground conditions: effect on tunnelling
Zones with extensive minor faulting wide fault zones containing gouge with
boulders;weak zones with collapse potential; and disturbed zones containing weakened
joint structures, heavily adverse geology and TBM tunnelling problems specific
adverse geological features and their effect on tunnelling machine operations, squeezing
ground, tunnel cave-ins: general characteristics encountering adverse ground
conditions.
8. Ground treatment in tunnelling
Ground control; general appreciation, weak cohesionless soils: water and instability
problems, ground treatment methods, dewatering using well bores electro-osmosis,
grouting,
ground
freezing,
investigation
procedures,
consolidation
grouting,
compaction grouting, jet grouting
9. Design and support of tunnels: operational criteria and principal support types
Temporary ground support, primary lining, secondary lining, requirements for tunnels,
ground classification in relation to tunnel, constructability, geotechnical design,
considerations, common support types used in civil engineering tunnels, mining
engineering tunnels, mining legislation, in situ stress common support types used in
mining, engineering tunnels, design methods: analytical methods, computational or
numerical methods, empirical methods,
10. Support of tunnels: rock reinforcement
Rock dowels, rock bolts, rock anchors, mechanisms of support, physical aspects of
rock reinforcement, ancillary items, influence of physical aspects of rock
reinforcement systems and their range of application, typical dimensions of rock bolt,
face plates, bond characteristics, role played by time in rock reinforcement,
installation technology, installation process.
11. Support of tunnels: concrete and shotcrete linings
Concrete Segmental Supports, Role of steel reinforcement of concrete segments,
Design and application aspects of precast concrete segmental linings, Yielding properties
of segmental concrete linings, Cast In Situ or Monolithic Concrete Linings,
Waterproofing of Concrete Linings, Shotcrete technology: operational and range of
application aspects, Shotcrete, General applications of shotcrete.
12. Support of tunnels: new austrian tunnelling method
Historical aspects of NATM, General Concepts of NATM, Principal historical
developments of NATM, NATM: Soft Ground Tunnelling Applications, Achieving
improved ground support control, Influence of stand-up time, Advantages of NATM
for soft ground tunnelling
13. Stresses and displacements associated with excavation of tunnels
Stresses in the Earth, Effect of Tunnel Formation on the Stress Field, Gravity Loading of
Near Surface Tunnels, Non-hydrostatic stresses, Rock Mass Failure and Displacements,
Interaction of tunnel stress fields
14. Design of tunnels: soft ground
Soft ground conditions, Soft ground tunnel design principles, General Design
Considerations, Effect of Lining Type on Design Methods, General lining design
considerations: soft ground tunnels, Cast iron linings, Tunnel Lining Design in Relation to
Shield Loading, Limitations of Numerical Design Techniques, Geotechnical data in
numerical design, Stress conditions and design approach, Stress-strain behaviour and
design aspects, Alternative Design Methods, Surface Subsidence Associated with Soft
Ground Tunnelling, Stability of tunnel heading in clay, Stability of tunnel heading in
clay.
15. Design of tunnels: rock conditions
Design of Tunnels with respect to Rock Structure, Rock mass structure considerations,
Rock mass structure: influence on tunnel stability, Rock Mass Classification Systems,
Rock load classification according to Terzaghi, RQD index as a qualitative description
of the rock mass, limitations and advantages, Lauffer-Pacher classification, Rock
structure rating (RSR), Geomechanics Classification: Rock Mass Rating (RMR),
Geomechanics Classification: Rock Mass Rating (RMR), NGl Tunnelling Quality
Index (Q System), General Comments on Application of Rock Mass Classification
Schemes, Comparison of Rock Mass Classification Schemes, Alternative Design
Approaches: Rock Structure Instability, Applications of Support to Controlling Rock
Mass Structural Features, Effect of excavation size, Design of Tunnels: Stress
Induced Closures and Instability, Significance of magnitude and orientation of stress
field, Rock Mass Behaviour, Homogeneity and anisotropy, Incorporation of Support
Characteristics into Numerical Design, Non-numerical Design Methods,Tunnel
Design and Stress Induced Instability and Closure