Railway, Bridge and Tunnel Engineering By Rangwala

4-3. Tractive effort of a locomotive
4-4. Track stresses
(1) Elastic theory
(2) Track modulus
(3) Forces acting on the railway track
4-5. Stresses in rails
(1) Lateral stresses
(2) Longitudinal stresses
(3) Contact shear stresses between rail and wheel
(4) Extra stresses
4-6. Determining track stresses
(1) Virtual wheel load
(2) Relief of stress
(3) Permissible stresses on a rail section
4-7. Stresses in sleepers
(1) Types of stresses in sleepers
(2) Factors depending stresses in sleepers
(3) Loads due to stresses in sleepers
4-8. Stresses in ballast
4-9. PRESSURE oN formation or subgrade
QUESTIONS 4

Chapter 5 RAILS

5-1. Functions or purposes of rails
5-2. Requirements of an ideal rail
5-3. Types of rails
(1) Double headed (D.H.) rails
(2) Bull headed (B.H.) rails
(3) Flat footed (F.F.) rails
5-4. Steel for rails
(1) Medium manganese steel
(2) High manganese steel
(3) Chromium steel
5-5. Weight of rails
(1) Cost
(2) Durability of track
(3) Waste of power
5-6. Standard sections of rails
5-7. Marking on rails
5-8. Corrugated or roaring rails
(1) Meaning
(2) Causes
(3) Occurrence
(4) Effects
(5) Types
(6) Peculiar properties
(7) Remedy
5-9. Corrosion of rails
(1) Quality of rail:
(2) Surface treatment
5-10. Length of rail
5-11. Welding of rails
(1) Theory
(2) Purposes
(3) Advantages of welding of rails
(4) Methods of welding
5-12. Wear of rails
(1) Wear of rails on top or head of rail
(2) Wear of rails at ends of rails
(3) Wear of rail on the sides of the head of rail
5-13. Methods to reduce wear of rails
(1) Use of special alloy steel
(2) Good maintenance of track

(3) Reduction of expansion gap
(4) Exchange of inner and outer rails on curves
(5) Introducing check rails
(6) Use of lubricating oil
(7) Head hardened rails
5-14. Measuring wear of rails
5-15. Renewal of rails
(1) Wear of rails
(2) Use of heavier locomotives
(3) Construction of branch lines
(4) Bending of rails
5-16. Failure of rails or defects in rails
(1) Crushed head
(2) Transverse fissure
(3) Split head
(4) Horizontal fissure
(5) Square or angular breaks
(6) Coning of wheels
(7) Hogged rails
(8) Buckling
5-17. Creep of rails
5-17-1. Causes of creep
(1) Brakes
(2) Wave action or wave theory
(3) Percussion theory
(4) Changes in temperature
5-17-2. Factors determining magnitude of creep
(1) Alignment of track
(2) Gradient of track
(3) Direction of motion of trains
(4) Embankments
(5) Weight and type of rail
5-17-3. Results of creep
5-17-4. Method of measuring the creep
5-17-5. Methods of correcting the creep
(1) Pulling back of rails method
(2) Use of creep anchors
(3) Use of steel sleepers
QUESTIONS 5

Chapter 6 SLEEPER

6-1. Functions of sleepers
6-2. Types of sleepers
(1) Longitudinal sleepers
(2) Transverse sleepers
6-3. Requirements of an ideal materi al for sleeper
6-4. Materials for cross-sleepers
6-4-1. Timber or wooden sleepers
(1) General
(2) Features of the wooden sleepers
(3) Requirements of wooden sleepers on girder bridges
(Bridge sleepers)
(4) Composite sleeper index (C.S.I.)
(5) Advantages of the timber sleepers
(6) Disadvantages of the timber sleepers
6-4-2. Steel sleepers
(1) Features of steel sleepers
(2) Conditions applied to design the steel sleepers
(3) Advantages of the steel sleepers
(4) Disadvantages of the steel sleepers
6-4-3. Cast-iron (C.I.) sleepers
(1) General
(2) Details of C.I. pot or bowl sleeper and C.I. plate sleeper
(3) Types of C.I. plate sleepers

(4) Features of the cast-iron sleepers
(5) Advantages of the cast-iron sleepers
(6) Disadvantages of the cast-iron sleepers
6-4-4. Concrete sleepers
(1) General
(2) Features of concrete sleepers
(3) Advantages of concrete sleepers
(4) Disadvantages of concrete sleepers
(5) Types of concrete sleepers
6-5. Sleepers for turnout
6-6. Sleeper density
6-7. Spacing of sleepers
6-8. Typical examples on sleepers
QUESTIONS 6

Chapter 7 BALLAST

7-1. Functions of ballast
7-2. Requirements of an ideal material for ballast
7-3. Materials used as ballast or types of ballast
(1) Broken stone
(2) Gravel
(3) Ashes or cinders
(4) Sand
(5) Kankar
(6) Moorum
(7) Brickbats
(8) Selected earth
7-4. Size and quantity of ballast
7-5. Renewal or Screening of ballast
7-6. Specifications for track ballast
(1) General Properties
(2) Physical Properties
(3) Size and gradation
(4) Shrinkage allowance
QUESTIONS 7

Chapter 8 TRACK FITTINGS

8-1. Rail joints
8-2. Avoidance of rail joints
8-3. Types of rail joints
(1) Types according to position of joints
(2) Types according to position of sleepers
8-4. Requirements of an ideal fastening
8-5. Fastenings for rails
8-6. Fish-plates
(1) Purpose
(2) Design of fish-plates
(3) Details
(4) Compound or junction fish-plates
(5) Failures of fish-plates
8-7. Spikes and bolts
8-7-1. Spikes
(1) Purpose of spikes
(2) Requirements of a good spike
(3) Types of spikes
8-7-2. Bolts
(1) Fang-bolts
(2) Hook-bolts or dog-bolts
(3) Fish-bolts
(4) Rag-bolts
8-8. Chairs and keys
8-9. Blocks
8-10. Bearing-plates
(1) Bearing area

(2) Rail-cutting
(3) Soil cutting on curves
(4) Stability
(5) Wear of spikes
(6) Maintenance
(7) Cost
8-11. Cotters and tie-bars
8-12. Pandrol-clip or elastic rail-clip
8-13. Summary
QUESTIONS 8

Chapter 9 GEOMETRIC DESIGN OF A TRACK

9-1. General
9-2. Necessity for geometric design of track
9-3. Objections to curvature of track
9-4. Radius and degree of curvature
9-5. Gradients
9-6. Types of curves
9-7. Transition curves
(1) Requirements of transition curve
(2) Forms of transition curve
(3) Length of transition curve
(4) Shift
9-8. Super-elevation or cant
9-9. Factors affecting super-elevation
(1) Frictional resistance
(2) Coning of wheels
(3) Body of the vehicle
(4) Weighted average
9-10. Speed of trains on curves
9-11. Cant Deficiency and Negative super-elevation
9-12. Cant Excess
9-13. Grade compensation on curves
9-14. Bending of rails on curves
9-15. Cutting of rails on curves
9-16. Widening of gauge on curves
9-17. Spirals for mountain railways
9-18. Switch-backs or zig-zag method
9-19. Rack railways
9-20. String-lining method of curves
9-21. Tilting train
(1) The Italian Pendolino
(2) The Spanish Talgo
(3) United aircraft turbo train
(4) Advanced passenger train
(5) X-2000
(6) Inter City Neigezug
QUESTIONS 9

Chapter 10 RESISTANCE TO TRACTION

10-1. Train resistances
(1) Resistance due to friction
(2) Resistance due to wave action or resistance dependent
on speed
(3) Resistance due to curves
(4) Resistance due to gradients
(5) Resistance due to speed of the train
(6) Resistance due to starting and acceleration
10-2. Rolling stock
10-2-1. Locomotives
(1) Definition
(2) Types of locomotives
(3) Essential parts of a locomotive
(4) Design of locomotive

(5) Classification
(6) Power of locomotive
10-2-2. Coaches
(1) Earlier coaches
(2) Modern coaches
(3) Double decker coaches
10-2-3. Wagons
(1) Timber truck wagon
(2) Cattle wagon
(3) Oil tank wagon
(4) Petrol tank wagon
(5) Hopper wagon
(6) Powder wagon
(7) Well wagon
(8) Refrigerated wagon
(9) Special wagons
10-3. Train-brakes
(1) Compressed air brakes
(2) Vacuum brakes
(3) Axle-mounted brake
(4) Magnetic brakes
10-4. Dynamometer car
(1) General
(2) Mechanisms
(3) Functions
(4) Points to remember
QUESTIONS 10

Chapter 11 POINTS AND CROSSINGS

11-1. Purpose
11-2. Some definitions
11-3. Sleepers laid for points and crossings
(1) Through sleepers
(2) Interlaced sleepers
11-4. Steel for points and crossings
11-5. Switches
(1) Stub switch
(2) Split switch
11-6. Shapes of switches
(1) Undercut switches
(2) Straight cut switches
(3) Over-riding switches or composite switches
11-7. Length of stock rails and tongue rails
11-8. Heel divergence or heel clearance
11-9. Switch angle
11-10. Throw of switch
11-11. Crossings
11-12. Types of crossings
(1) Ordinary or acute crossing
(2) Double or obtuse crossing
11-13. Theoretical nose of crossing (T.N.C.) and actual nose of
crossing (A.N.C.)
11-14. Crossing clearance
11-15. Crossing number
11-16. Crossing angle
(1) Right angle or Cole’s method
(2) Centre-line method
(3) Isosceles triangle method
11-17. Different types of leads and their calculations
11-18. Laying of points and crossings
(1) Where there is no traffic interruption as in case of a
new turnout
(2) Under traffic where the line is available for a few hours only
11-19. Maintenance of points and crossings

11-20. Combinations of points and crossings
11-20-1.Cross-overs
11-20-2.Scissors cross-overs
11-20-3.Slips
11-20-4.Fixed point
11-20-5.Three throws
11-20-6.Tandems or double turnouts
11-20-7.Gathering lines or ladder tracks
11-20-8.Gauntlet tracks
11-20-9.Double junctions
QUESTIONS 11

Chapter 12 RAILWAY STATIONS AND YARDS

12-1. General
12-2. Definition of a station
12-3. Purposes of a railway station
12-4. Selection of site for a railway station
12-5. Facilities required at railway stations
(1) Public requirements
(2) Traffic requirements
(3) Requirements of locomotive department
(4) General requirements
12-6. Classification of stations
12-6-1. Operational classification
(1) Block stations
(2) Non-block or D class stations
(3) Special class stations
12-6-2. Functional classification
(1) Wayside stations
(2) Junctions
(3) Terminals
12-7. Platforms
(1) Passenger platforms
(2) Goods platforms
12-8. Staff quarters
12-9. Goods traffic at wayside stations
Case I
Case II
12-10. Catch sidings
12-11. Definition of a yard
12-12. Types of yards
12-12-1.Passenger yards
12-12-2.Goods yards
12-12-3.Marshalling yards
(1) General
(2) Design of marshalling yards
(3) Features of marshalling yards
(4) Types of marshalling yards
12-12-4.Locomotive yards
12-13. Level-crossing
12-14. Ash-Pits, Ash-Pans And Examination Pits
12-15. Drop pits
12-16. Water columns
12-17. Triangles
12-18. Turntables
QUESTIONS 12

Chapter 13 SIGNALLING AND INTERLOCKING

13-1. Objects of signalling
13-2. Classification of signals
13-2-1. Classification according to function
(1) Stop signals or semaphore type signals
(2) Warner signals
(3) Disc or ground signals

(4) Coloured light signals
13-2-2. Classification according to location
(1) Outer signal
(2) Home signal
(3) Starter signal
(4) Advance starter signal
13-2-3. Special signals
(1) Routing signals
(2) Repeating signals
(3) Co-acting signals
(4) Calling-on signals
(5) Indicators
(6) Miscellaneous signals
13-3. Typical layouts
(1) Signalling at diverging junction
(2) Signalling at converging junction
(3) Signalling at a junction of two main lines and two branch
lines with a siding
13-4. Various signalling systems
(1) Following trains system
(2) Absolute block system
(3) Automatic signalling
(4) Pilot guard system
(5) Centralized traffic control system
(6) Cab signalling system
(7) TGV signalling system
13-5. Interlocking
13-5-1. Essential principles of interlocking
13-5-2. Methods of interlocking
(1) Tappets and locks system
(2) Key system
(3) Route relay system (RRS)
13-5-3. Slotting of signals
(1) Meaning of the term
(2) Principles
(3) Purposes
(4) Methods
13-5-4. Detectors
13-5-5. Point lock and treadle or lock bar
13-5-6. Interlocking of level-crossings
13-5-7. Interlocking standards
(1) Automatic signalling
(2) Grouping of levers
(3) Interlocking
(4) Isolation of main line
(5) Large stations
(6) Starting signals
13-5-8. Improvements in interlocking and signalling
QUESTIONS 13
Section II : BRIDGE ENGINEERING

Chapter 14 CONSTRUCTION AND DRAINAGE OF
RAILWAY TRACK

14-1. General
14-2. Usual forms of cross-sections
14-3. Features of railroad bed level
(1) Width of formation
(2) Slopes of sides
(3) Drains
(4) Method of construction
14-4. Drainage
(1) Action of water
(2) Importance of drainage
(3) Requirements of drainage system
14-5. Stabilization of track on poor soil

(1) Layer or blanket of moorum or sand
(2) Cement grouting
(3) Sand piles
(4) Use of chemicals
(5) By providing capillary break or cut-off
QUESTIONS 14

Chapter 15 MAINTENANCE, ACCIDENTS AND SAFETY

15-1. General
(1) Foundations
(2) Nature of structure
15-2. Necessity for maintenance of track
(1) New track
(2) Constant use
15-3. Maintenance of track proper
(1) Duties of a gangmate or a ganger
(2) Duties of a keyman
(3) Duties of a Permanent Way Inspector (P.W.I.)
15-4. Maintenance of railway bridges
15-5. Maintenance of rolling stock
15-6. Signalling during maintenance
15-7. Packing of ballast and sleepers
15-8. Rail inspection
15-9. Track inspection
15-10. Maintenance and boxing of ballast
15-11. Track imprest
15-12. Track work for high speeds
15-13. Speeds on the Indian railways
(1) Brakes and signals
(2) Cattle and trespassers
(3) Curves
(4) Deterioration of track and rolling stock
(5) Dust nuisance
(6) Energy consumption
(7) Level-crossings
(8) Locomotives
(9) On-board facilities in trains
(10) Sharing of routes
15-14. Emergency measures
(1) Diversions
(2) Ash or selected earth
(3) Temporary supports
(4) Scouring
(5) Wagons with rubble
(6) Breakdown vans
15-15. Accidents
(1) General
(2) Causes of accidents
(3) Points to be observed at the time of accident
15-16. Safety measures to avoid train accidents
(1) Safety camps
(2) Safety organization
(3) Propaganda campaign
(4) Rewards
(5) Psychological and other tests
(6) Proper maintenance of track
(7) Bumps near level-crossings
(8) Road surface
(9) Warning signs
(10) Visibility
(11) Speed
(12) Standards
(13) Warning bells

(14) Flashing red lamps
(15) Train detection scheme
(16) Human factors
QUESTIONS 15

SECTION II: BRIDGE ENGINEERING
Chapter 16 INTRODUCTION

16-1. General
16-2. Importance of bridges
16-3. Identification of bridges
16-4. Requirements of an Ideal Bridge
16-5. Selection of bridge site
(1) Connection with roads
(2) Freeboard
(3) Firm embankments or river banks
(4) Foundations
(5) Large tributaries
(6) Materials and labour
(7) Minimum obstruction to waterway
(8) Right-angle (square) crossing
(9) Scouring and silting
(10) Straight stretch of river
(11) Velocity of flow
(12) Width of river
16-6. Preliminary data to be collected for bridge project
16-7. Stages of investigation
(1) Reconnaissance or technical feasibility stage
(2) Preliminary or techno-economic feasibility stage
(3) Detailed survey and project report stage
16-8. Preliminary and final project drawings
(1) Catchment area map
(2) Contour plan
(3) Cross-sections
(4) Index map
(5) Longitudinal section
(6) Soil profile
16-9. Choice of bridge type
(1) Approaches
(2) Availability of funds
(3) Climatic conditions
(4) Economy in construction
(5) Foundations
(6) Navigational requirements
(7) Specialized firm
(8) Type of traffic
16-10. Components of a bridge
(1) Sub-structure
(2) Super-structure
(3) Adjoining structures
16-11. Approaches of bridge
(1) Borrow pits
(2) Construction
(3) Cost
(4) Curvature
(5) Extension of bridge
(6) Gradient
(7) Joint walls
(8) Maintenance
(9) Width and length
16-12. Economic span of a bridge
(1) Definition
(2) Assumptions
(3) Exceptions

16-13. Number of spans of a bridge
(1) Alternative proposals
(2) Foundations for piers
(3) Odd number of spans
(4) Span
16-14. Afflux
(1) Definition
(2) Importance
(3) Height of afflux
16-15. Clearance and freeboard
(1) Definition
(2) Necessity
(3) Provisions
16-16. Maximum flood discharge or High flood level (H.F.L.)
16-17. Length of a bridge
16-18. Grip Length
16-19. Linear Waterway of a bridge
16-20. Bridge Alignment
(1) Alignment on curve
(2) Control of highest flood level
(3) Effects of silting and scouring
(4) Layout of approaches
(5) River training works
(6) Skew bridges
16-21. Joints of bridge
(1) Construction joints
(2) Expansion and contraction joints
16-22. Handrails
(1) Panel slab and post system
(2) Post and rail system
16-23. River Training works
(1) Objects
(2) Methods
QUESTIONS 16

Chapter 17 BRIDGE FOUNDATIONS

17-1. General
17-2. Essential requirements of a good foundation
(1) Location
(2) Stability
(3) Settlement
17-3. General principles of design of bridge foundations
(1) Bearing capacity of soil
(2) Frictional resistance
(3) Scour depth
17-4. Subsoil exploration
(1) Test pits
(2) Probing
(3) Auger boring
(4) Wash boring
(5) Test piles
(6) Deep boring
(7) Geophysical method
17-5. Testing of soil samples
(1) Plate bearing test
(2) Standard penetration test (SPT)
(3) Vane shear test
17-6. Types of foundations
17-7. Spread foundations
17-8. Pile foundations
(1) General:
(2) Requirements for pile foundation
(3) Types of piles

17-9. Caissons and Cofferdams
(1) Caissons
(2) Cofferdam
17-9-1. Classification of caissons
17-9-2. Materials used for the construction of caissons
(1) Cast-iron
(2) Reinforced cement concrete
(3) Steel
(4) Timber
17-9-3. Requirements of a cofferdam
17-9-4. Uses of caissons
17-9-5. Uses of cofferdams
17-9-6. Types of cofferdams
(1) Dikes
(2) Single wall cofferdams
Construction of single wall cofferdam
(3) Double wall cofferdams
(4) Cellular cofferdams
(5) Rock-filled crib cofferdams
(6) Concrete cofferdams
(7) Suspended cofferdams
17-9-7. Prevention of leakage in cofferdams
17-9-8. Factors affecting design of a cofferdam
17-9-9. Difference between cofferdam and caisson
Questions 17

Chapter 18 SUB-STRUCTURES

18-1. General
18-2. Abutments
(1) Definition
(2) Functions
(3) Types of abutments
(4) Forces acting on an abutment
(5) Conditions of stability
(6) Dimensions
18-3. Piers
(1) Definition
(2) Function
(3) Types of piers
(4) Forces acting on a pier
(5) Conditions of stability
(6) Dimensions
(7) Location
(8) Abutment pier
18-4. Wing walls
(1) Definition
(2) Functions
(3) Types of wing walls
(4) Forces acting on a wing wall
(5) Conditions of stability
(6) Dimensions
(7) Precautions
18-5. Setting out for piers and abutments
(1) Bench marks
(2) Positions of reference points
(3) Principal reference lines
(4) Replacing original points
18-6. Materials for sub-structures
(1) Cement concrete
(2) Masonry
(3) Steel
18-7. Bridge Inspection
QUESTIONS 18

Chapter 19 CLASSIFICATION OF BRIDGES

19-1. History of bridge development
(1) Arch bridges
(2) Suspension bridges
(3) Simply supported bridges
(4) Truss and girder bridges
19-2. Classification Of Bridges
19-3. Bridges According to material used
(1) R.C.C. and pre-stressed cement concrete bridges
(2) Brick or stone masonry bridges
(3) Steel bridges
(4) Timber bridges
(5) Composite bridges
19-4. bridges According to the position of bridge floor
(1) Deck bridges
(2) Through bridges
(3) Semi-through bridges:
19-5. bridges According to the inter span relations
(1) Simple bridges or beam bridges
(2) Continuous bridges
(3) Simple cantilever bridges
(4) Balanced type cantilever bridge
19-6. bridges According to the type of super-structure
(1) Arch bridges
(2) Bow-string girder bridges
(3) Rigid frame bridges
(4) Suspension bridges
(5) Advantages and disadvantages of suspension bridges
(6) Cable-stayed bridges
19-7. bridges According to the method of clearance for navigation
(Movable bridges)
(1) Bascule bridges
(2) Cut-boat bridges
(3) Lift bridges
(4) Swing bridges
(5) Transporter bridges
(6) Traversing bridges
(7) Flying bridges
19-8. Bridges According to the length of span or as per linear
waterway
(1) Arch culverts
(2) Box culverts
(3) Pipe culverts
(4) Slab culverts
(5) Scuppers
19-9. Bridges According to the road level relative to highest flood
level (H.F.L.)
(1) Submersible bridges or causeways
(2) Non-submersible bridges
19-10. Bridges According to life of super-structure
(1) Permanent bridges
(2) Temporary bridges
19-10-1.Temporary Bridges with intermediate supports
(1) Crates
(2) Cribs
(3) Pile bents
(4) Trestles
19-10-2.Temporary Bridges without intermediate supports
(1) Cantilevers
(2) Suspension bridges
(3) Trusses
19-10-3.Temporary Floating bridges
(1) Boat bridges

(2) Pontoon bridges
(3) Raft bridges
19-11. Bridges According to flexibility of super-structure
(1) Fixed span superstructure
(2) Movable span superstructure
19-12. Bridges According to the alignment
19-13. Bridges According to level of crossing of highways and
railways
(1) Over bridge
(2) Under bridge
19-14. Bridges According to method of connections adopted for
different parts of super structure
(1) Pinned connection bridge
(2) Riveted connection bridge
(3) Welded connection bridge
19-15. Bridges According to the function of a bridge
(1) Aqueduct bridge (canal over a river)
(2) Viaduct (road or railway over a valley or river)
(3) Pedestrian bridge
(4) Highway bridge
(5) Railway bridge:
(6) Road-cum-rail or pipe line bridge
19-16. Bridges according to the degree of redundancy
(1) Determinate bridge
(2) Indeterminate bridge
19-17. Bridges according to the loading
Questions 19

Chapter 20 BRIDGE FLOORING

20-1. General 453
20-2. Factors affecting the choice of Flooring material
20-3. Requirements of a good flooring material
20-4. Types of floors
(1) Open floors
(2) Solid floors
20-5. Flooring materials
(1) Jack arch
(2) Mild steel buckle plates
(3) Mild steel plates
(4) Mild steel troughs
(5) Reinforced cement concrete
(6) Timber
20-6. Drainage of floors
QUESTIONS 20

Chapter 21 BRIDGE BEARINGS

21-1. Definition
21-2. Purposes or functions of bearings
21-3. Importance of bearings
21-4. Free and fixed bearings
21-5. Types of bearings
(1) Cement mortar pad
(2) Expansion bearing
(3) Knuckle bearing
(4) Rocker and roller bearing
(5) Rocker bearing
(6) Rubber bearing
(7) Neoprene bearing pads
(8) Sliding bearing
(9) Sole plate on curved bed plate bearing
(10) Tar paper bearing
(11) Pin bearing
(12) Pot bearing
(13) Laminated elastomeric bearing

21-6. Materials for bearings
21-7. Bed blocks
21-8. Maintenance of bearings
QUESTIONS 21

Chapter 22 DESIGN OF BRIDGES

21-1. Definition
21-2. Purposes or functions of bearings
21-3. Importance of bearings
21-4. Free and fixed bearings
21-5. Types of bearings
(1) Cement mortar pad
(2) Expansion bearing
(3) Knuckle bearing
(4) Rocker and roller bearing
(5) Rocker bearing
(6) Rubber bearing
(7) Neoprene bearing pads
(8) Sliding bearing
(9) Sole plate on curved bed plate bearing
(10) Tar paper bearing
(11) Pin bearing
(12) Pot bearing
(13) Laminated elastomeric bearing
21-6. Materials for bearings
21-7. Bed blocks
21-8. Maintenance of bearings
QUESTIONS 21
Chapter 22 DESIGN OF BRIDGES
22-1. General
22-2. Buoyancy pressure
22-3. Centrifugal forces
(1) Road bridges
(2) Railway bridges
22-4. Dead load
(1) Unwin’s formula
(2) American formula for plate girders
(3) American formula for trusses
(4) R.C.C. arches
(5) R.C.C. slab bridges upto 6 m span
(6) R.C.C. slab and T beam bridges
22-5. Deformation stresses
22-6. Earth pressure
22-7. Erection stresses
22-8. Impact load
(1) For road bridges
(2) For railway bridges
22-9. Live load
(1) For road bridges
(2) For railway bridges
22-10. Longitudinal forces
(1) For road bridges
(2) For railway bridges
22-11. Secondary stresses
(1) In case of R.C.C. structures
(2) In case of steel structures
22-12. Seismic load
22-13. Temperature variation forces
(1) Concrete structures
(2) Metal structures
(3) Temperature variation
22-14. Water pressure
22-15. Wind load
(1) For road bridges
(2) For railway bridges
22-16. Design of bridge foundations
22-17. Forces acting on different components of a bridge
(1) Forces acting on foundation
(2) Forces acting on abutments
(3) Forces acting on piers
(4) Forces acting on wing walls
(5) Forces acting on super-structures
QUESTIONS 22

Chapter 23 CONSTRUCTION AND ERECTION METHODS OF BRIDGE

23-1. General
(1) Centering
(2) Field forces
(3) Machinery
(4) Measurement of span
(5) Selection of method
23-2. Erection of steel girders
(1) Building out from supports
(2) Floating
(3) Lifting
(4) Rolling

(5) Staging
23-3. Erection of Steel Truss Bridges
(1) First stage
(2) Second stage
(3) Third stage
(4) Fourth stage
23-4. Erection of Suspension Bridges
(1) Erection of towers
(2) Erection of suspenders
(3) Erection of catwalks
(4) Erection of stiffening trusses
(5) Erection of flooring system
23-5. Construction of Pre-Stressed Concrete Super-Structure
23-6. Erection of R.c.c. And Pre-Stressed Girder Bridges
(1) Cast-in-situ construction on staging
(2) Segmental cantilever construction using cast-in-situ or
precast segments
(3) Span by span method
(4) Incremental launching method
(5) Movable form system or movable scaffold system
23-7. Formwork for arch bridges
(1) Good features
(2) Types
QUESTIONS 23

Chapter 26 TUNNELLING IN HARD ROCK

26-1. General
26-2. Sequence of operations for tunnelling in rock
26-3. Faces of attack for tunnelling in rock
26-4. Methods of tunnelling in rock
26-5. Mucking
26-6. Hauling
26-7. Safety precautions in rock tunnelling
QUESTIONS 26

Chapter 24 TESTING, STRENGTHENING AND MAINTENANCE OF BRIDGES

24-1. General
24-2. DETERIORATION OF BRIDGES
24-3. Bridge Failures
24-4. Defects of bridges and their rectification
(1) Cracks in concrete
(2) Corrosion of structural steel work
(3) Other defects of bridge
24-5. Inspection of bridges
(1) Detailed inspection
(2) Routine inspection
24-6. Posting of bridges
(1) Load limit postings
(2) Speed postings
24-7. Rating of existing bridges
(1) Magnetic particle detector
(2) Radiographic equipment
(3) Ultrasonic testing equipment
24-8. Rebuilding of bridges
(1) Damage
(2) Excessive maintenance cost
(3) Obsolescence
(4) Weathering
24-9. Testing and strengthening of bridges
(1) Correlation method
(2) Load testing
(3) Theoretical method
24-10. Maintenance of the bridges
QUESTIONS 24

SECTION III TUNNEL ENGINEERING
Chapter 25 GENERAL ASPECTS OF TUNNELLING

25-1. General
(1) Tunnel
(2) Open cut
(3) Bridge
(4) Surface road
25-2. Advantages and disadvantages of tunnelling

(1) Advantages of tunnelling (Necessity of tunnels)
(2) Disadvantages of tunnelling
25-3. Advantages and disadvantages of open cuts
(1) Advantages
(2) Disadvantages
25-4. Classification of tunnels
(1) Classification of tunnels according to alignment
(2) Classification of tunnels according to purpose
(3) Classification of tunnels according to type of material
met with in the construction
25-5. Shapes of tunnels
(1) D-section or segmental roof section
(2) Circular section
(3) Rectangular section
(4) Elliptical section
(5) Horse-shoe section
(6) Egg-shaped section
25-6. Comparison of bypassing Alternatives Tunnel, Open cut,
bridge and surface road
25-7. Size of tunnels
25-8. Problems IN tunnelling
QUESTIONS 25

Chapter 26 ALIGNMENT OF TUNNEL

26-1. Alignment of a tunnel
(1) Alignment restraints
(2) Environmental considerations
26-2. Investigations for tunnel site
(1) Investigations before planning
(2) Investigations at the time of planning
(3) Investigations at the time of construction
26-3. Setting out of tunnel
(1) Setting out tunnel on ground surface
(2) Transfer of centre line from surface to underground
(3) Underground setting out
(4) Underground levelling
26-4. Excavation
(1) Drilling of holes
(2) Selection of drilling equipment
(3) Types of mounts
26-5. Excavation of tunnels in rock with machines
26-6. Blasting
(1) Types of explosives
(2) Cuts
(3) Theory of blasting
(4) Quantity of rock released
26-7. Supplementary operations
(1) Checking of soundness of freshly cut surface
(2) Contour trimming
(3) Sealing of cracks, weak zones, etc.
26-8. Miscellaneous
(1) Progress of tunnelling work
(2) Procedure of work
(3) Emergency services
QUESTIONS 26

Chapter 29 LIGHTING, VENTILATION AND DUST CONTROL
IN TUNNELS

29-1. Tunnel lighting
29-1-1. Spacing of lights
29-1-2. Types of tunnel lights
29-2. Ventilation in tunnels
29-2-1. Objects of tunnel ventilation
29-2-2. Requirements of tunnel ventilation
29-2-3. Volume of air required
29-2-4. Methods of ventilation
29-2-5. Equipments for ventilation
29-2-6. Permanent ventilation
29-3. Dust control
QUESTIONS 29

Chapter 27 SHAFTS AND PORTALS

27-1. General
27-2. Advantages of shafts
27-3. Size of shafts
27-4. Location of shafts
(1) Shafts over centre-line
(2) Side shafts
27-5. Classification of shafts

(1) Temporary shafts
(2) Permanent shafts
(3) Vertical shafts
(4) Inclined shafts
27-6. Construction of shafts in rock
(1) Drilling and blasting
(2) Mucking
(3) Timbering
(4) Pumping
(5) Raising
27-7. Construction of Shafts in soft SOIL
(1) Shallow shafts in soft soil – Method of sinking:
(2) Deep shafts in soft soil:
27-8. Design of shaft supports
27-9. Precautions for shaft sinking work in soft soil
27-10. Protection round the shaft opening
27-11. Portals
27-12. Twin tunnels
QUESTIONS 27

Chapter 28 TUNNELLING IN HARD ROCK

28-1. General
28-2. Sequence of operations for tunnelling in rock
28-3. Faces of attack for tunnelling in rock
(1) System of vertical shafts
(2) System of pilot tunnels
28-4. Methods of tunnelling in rock
(1) Drift method
(2) Heading and bench method
(3) Full face method
(4) Cantilever car dump method
28-5. Mucking
28-6. Mucking in steep grade tunnelling
28-7. Hauling
28-8. Safety precautions in rock tunnelling
QUESTIONS 28

Chapter 28 TUNNELLING IN HARD ROCK

29-1. Soil classification
29-2. Choice of method
(1) Equipment available
(2) Method of sequence of excavation
(3) Size of tunnel
(4) Type of ground
29-3. Methods of tunnelling in soft soil
29-4. Forepoling method
29-5. Needle beam method
29-6. Army method or case method
29-7. American method
29-8. English method
29-9. Belgian method
29-10. German method
29-11. Austrian method
29-12. Liner plates method
(1) Liner plates with stiffening ribs
(2) Liner plates without stiffening ribs
(3) Uses of liner plates with ribs
29-13. Tunnelling with shield
(1) Shield
(2) Dimensions of shield
29-13-1.Parts of shield
(1) Cutting head or leading head
(2) Central part or trunk portion
(3) Tail or rear portion

29-13-2.Terms commonly used with shield
(1) Shove of shield
(2) Length of shove
(3) Open shove
(4) Partially blind shove
(5) Blind shove
29-13-3.Primary lining in shield
(1) General
(2) Requirements for primary lining
29-13-4.General steps of tunnelling with shield
29-13-5.Shield tunnelling in different types of soils
29-13-6.Common Equipment with shield
(1) Supporting means or supporting equipment
(2) Gravel tank
(3) Chute
(4) Trailing dam
29-13-7.Sequence of tunnelling using the shield
(1) Excavation
(2) Mucking and hauling
(3) Advancement or shoving
(4) Installation of primary lining
(5) Grouting caulking and drainage
29-14. Cut and cover method
29-14-1.Salient features of cut and cover method
29-14-2.Types of construction methods
(1) Bottom-up construction method
(2) Top-down construction method
29-15. Timbering in soft soil tunnelling
QUESTIONS 29

Chapter 30 TUNNEL BORING MACHINE

30-1. Mechanized shields
(1) Rotary wheel type mechanised shield
(2) Planetary cutting assemblies
(3) Oscillatory type mechanized shield
(4) Auger head cutting assemblies
(5) Active horizontal shelf shield
(6) Water jets
30-2. Mechanised Tunnel boring machine
(1) General
(2) Types of mechanized tunnel boring machine
(3) Advantages of mechanized tunnelling
(4) Disadvantages of mechanized tunnelling
30-3. Factors for Selection of Tunnel boring machine
30-4. Sequence of mechanised tunnel boring machine
30-5. Difference between open type TBM and closed type shield TBM
30-6. Difference between single shield TBM and double shield TBM
Questions 30

Chapter 31 NEW AUSTRIAN TUNNELLING METHOD (NATM)[SEQUENTIAL EXCAVATION METHOD]

31-1. Introduction to NATM
31-2. Objectives of NATM
31-3. FEATURES of NATM
(1) Mobilization of the strength of rock mass
(2) Shotcrete protection
(3) Measurements and monitoring
(4) Flexible support
(5) Closing of invert
(6) Contractual arrangements
(7) Rock mass classification determines support measures
31-4. Components And Sequence Of Execution In Natm
(1) Survey and profile marking
(2) Forepoling

(3) Face drilling
(4) Charging and blasting
(5) De-fuming
(6) Mucking
(7) Scaling and chipping
(8) 3D monitoring targets installation
(9) Face sealing shotcrete
(10) Fixing of wire mesh
(11) Rock bolting
(12) Grouting
(13) Primary lining with shotcrete
(14) Fixing of lattice girders
(15) Second layer of shotcreting
(16) Waterproofing
(17) Final lining
31-5. Conclusions
Questions 31

Chapter 32 TUNNEL LINING

32-1. Necessity of lining
32-2. Objects of tunnel lining
32-3. Materials for lining
(1) Masonry for lining of tunnel
(2) Stone masonry for lining of tunnel
(3) Cement concrete for lining of tunnel
(4) Timber for lining of tunnel
(5) Cast-iron for lining of tunnel
32-4. Design of thickness of lining
(1) General
(2) Timber lining
(3) Concrete lining
32-5. The Sequence Of Lining A Tunnel
(1) Placing the entire lining in one operation
(2) Placing the invert first and the rest of the lining next
(3) Placing the invert first, the sides next and finally the roof
(4) Placing side walls first, then roof and finally invert
(5) Curbs installed at the sides first, then walls and roofs
and finally invert
QUESTIONS 32

Chapter 33 LIGHTING, VENTILATION AND DUST CONTROL IN TUNNELS

33-1. Tunnel Lighting

33-1-1. Spacing of lights
33-1-2. Types of tunnel lights
(1) Lanterns and lamp burning oil
(2) Coal gas lighting
(3) Acetylene gas lighting
(4) Electric lighting
33-2. Ventilation in tunnels
33-2-1. Objects of tunnel ventilation
33-2-2. Requirements of tunnel ventilation
33-2-3. Volume of air required
33-2-4. Methods of ventilation
(1) Natural ventilation
(2) Mechanical ventilation
33-2-5. Equipment required for tunnel ventilation
(1) Fans for tunnel ventilation
(2) Pipes for tunnel ventilation
33-2-6. Permanent ventilation and noise pollution
(1) Permanent ventilation
(2) Permanent ventilation for long tunnels
(3) Systems or methods of permanent ventilation
(4) Noise pollution
33-3. Dust control and methods
(1) Dust control
(2) Dust control methods
QUESTIONS 33

Chapter 34 DRAINAGE IN TUNNELS

34-1. General
34-2. Pre-drainage
34-3. Dewatering
34-4. Permanent drainage
QUESTIONS 34

Chapter 35 SAFETY IN TUNNEL CONSTRUCTION

35-1. General
35-2. Safety precautions in tunnelling
35-3. Health protection in tunnel construction
(1) Protection from Silicosis
(2) Protection from Caisson diseases
Questions 35

APPENDICES
Appendix I ABBREVIATED TERMS
Appendix II GTU EXAMINATION PAPERS
INDEX