This document provides an overview of a course on fundamentals of tunnel engineering, planning, design, and technology taught by Prof. Dr. Hassan Fahmy for B.Sc Mining Engineering students. The course covers definitions of tunnels, the planning stage including site exploration and investigations, the design stage including stress analysis and support design, and excavation methods. Figures are included showing examples of tunnel construction challenges and support methods.

1. Course in fundamentals of tunneling,
engineering planning ,design and technology.
Prof.Dr. Hassan Fahmy
B.Sc, Mining Engineering students.

2. Course in fundamentals of tunneling,
engineering planning ,design and technology.
Prof.Dr. Hassan Fahmy
B.Sc, Mining Engineering students.
I. Definitions
•Geologic definition of tunnel.
•Engineering definition of tunnel.
•Engineering tunnel components.
•Tunnel engineering.
•Planning stage. Goals and limitation.
•Design stage.
•Excavation stage.
•Economy.
•Tunnel as subsurface construction.
•Influence of rock media.
•Geologic setting.
•Subsurface geologic mapping.
•Geologic structure.
•Underground water.

3. II. Planning stage
a) General:
•Goals (mining ,traffic , military , water cond. ,power generation etc…….
•Sites exploration and selection.
•Site investigation.
•Lab and field tests.
•Subsurface map.
•Planning of tunnel axis route depth , slopes, alignment …. Etc .
•Planning of tunnel cross section shape and size .
b) Cross section arrangement. ( size )
•Traffic tunnels.
•Mining tunnels.
•Water-waste tunnels.
•Military tunnels.
•Water tunnels.
•Ventilation tunnels.
c) Planning of tunnel axis and depth
•Goals of tunnel
•Traffic and transportation means , topography ,subsurface geology ,method of material handling in mining, type
of mineralization etc….
•Subsurface geologic status of site
•Rock structures and their impacts
•Under ground water conditions
•Subsurface infrastructures

4. General design methodology:
Planning and design of
tunnel underground
opening
Plannin
g
Cross-sectionLongitudinal profileAxis
Auxiliary operation Design
Supports
and
treatment
Load calculation
And
Stability analysis
Excavation
Site
investigation

5. Axis Choice
Purpose
Water
Tunnels
Mining
Operations Railway
Surface
Topography
Geotechnical
Conditions
Geological
Conditions
Type Of
Rocks
Hard Soft Loose
Geologic
Structures
Folds Faults Joints
Hydrologic
Conditions
Properies Of
Rocks
Compressive
Strength
Tensile
Strength
Bending
Water
Content

6. Longitudinal Profile Choice
Porpose
Traffic
Tunnels
Water
Tunnels
Mining
Openings
Location Of
Portals
At The
Surface
At Certain
Depth
Geotechnical
Properties
Hydrological
Conditions
Underground
Water
Surface Water
Properties Of
Rocks
Compressive
Strength
Tensil
Strength
Water
Content
Geological
Properties
Geologic
Structures

7. cross-section
shape of the
cross-section
circular rectangular trapizoidal square
size of the
cross-section

13. Stress distribution in regularly jointed anisotropic rock.
[ fromgaziev and erlikman (1971). ]

15. Tunnel sections arrangement

16. 1)Traffic tunnels

23. 2. Tunnels for power

24. III. Design stage
a) Generals
• Stress at appoint, stress vector, vector field.
• Stress field.
• Rock properties (lab tests, instue tests).
• Rock behavior.
• IN tack rock.
• Rock mass.
• Rock media characteristics.
Geologic setting.
Influencing parameters.
b) Design loads
• Sources
Sources of earth stress field (primitive)
 Gravitation of force.
 Centrifugal force due to earth rotation.
 Evasion and denudation.
 Tide.
 Seismic and seismic-like activities.
 Others.
• Induced (secondary) stress field
Tunneling activities.
U.g structural activities such as mining, power generation, atomic activation.
Human activities.
• Primitive stress analysis.
Assumptions ,complexity of the problem ,diversity of calculation concepts.

33. Stress analysis around
Tunnel sections

50. Tunnel support, subsidence, and technology

60. Behavior Of Rocks

73. Figure 1 : The Vajont dam during impounding of the reservoir. In the middle distance, in the
centre of the picture, is Mount Toc with the unstable slope visible as a white scar on the
mountain side above the waterline.

74. Figure 2 : During the filling of the Vajont reservoir the toe of the slope on Mount Toc was
submerged and this precipitated a slide. The mound of debris from the slide is visible in the
central part of the photograph. The very rapid descent of the slide material displaced the water in
the reservoir causing a 100 m high wave to overtop the dam wall. The dam itself, visible in the
foreground, was largely undamaged.

75. Figure 3 : The town of Longarone, located downstream of the Vajont dam, before the
Mount Toc failure in October 1963.

76. Figure 4 : The remains of the town of Longarone after the flood caused by the
overtopping of the Vajont dam as a result of the Mount Toc failure. More than 2000
persons were killed in this flood.

77. Figure 5 : The results of a rockburst in an underground mine in
brittle rock subjected to very
high stresses.

78. Figure 6 : A wedge failure controlled by
intersecting structural features
in the rock mass forming the bench of an open
pit mine.

79. Figure 7 : Disking of a 150 mm core of granite
as a result of high in situ stresses.

80. Figure 8 : Installation of steel lining in a pressure tunnel in a hydroelectric project.

81. Figure 9 : An example of poor blasting in a tunnel.

82. Figure 10 : An example of good blasting in a tunnel.

83. Figure 11

84. Figure 12 : Ravelling of small wedges in a closely jointed rock mass.
Shotcrete can provide effective support in such rock masses.

85. Figure 13 : The 12 m span 8 m high top heading for the tailrace tunnel
was constructed by full-face drill-and-blast and, because of the excellent
quality of the massive gneiss, was largely unsupported.

86. Figure 14: A wedge failure in the roof of the top heading
of the Rio Grande tailrace tunnel.

87. Figure 15 : A 6 m wide heading driven ahead of the tunnel face to permit
pre-reinforcement of potentially unstable wedges in the roof. The seven-
boom jumbo is seen working in the heading.

88. Figure 16 : Drilling vertical diamond core holes into the Sau Mau Ping slope.
These holes were used for geotechnical investigation purposes and also for
the installation of piezometers in the rock mass.

89. Figure 17: A rock slope on a mountain highway.
Rockfalls are a major hazard on such highways.

90. Figure 18 : An example of good blasting in a tunnel. Geobrugg ring net shown restraining
a boulder. These nets can be designed with energy absorbing capacities of up to 2500
kNm which is equivalent to a 6 tonne boulder moving at 20 m per second.

91. Figure 19 : Comparison between the results achieved using controlled blasting (on the left)
and normal bulk blasting for a surface excavation in gneiss.

92. Figure 20 : Partially completed 20 m
span, 42.5 m high underground
powerhouse cavern of the Nathpa
Jhakri Hydroelectric Project in
Himachel Pradesh, India. The cavern is
approximately 300 m below the
surface.

93. Figure 21 : Isometric view of the 3DEC4 model of the
underground powerhouse cavern and transformer gallery of the
Nathpa Jhakri Hydroelectric Project, analysed by Dr. B. Dasgupta5.

94. Figure 22 : Large displacements
in the top heading of the headrace
tunnel of the Nathpa Jhakri
Hydroelectric project. These
displacements are the result of
deteriorating rock mass quality
when tunnelling through a fault
zone

95. Figure 23 : Side drift in the
Athens Metro Olympion
station excavation that was
excavated by the method
illustrated in Figure 11.25. The
station has a cover depth of
approximately 10 m over the
crown

96. Figure 24 : Assembly of a friction joint in a top hat section steel set.

97. Figure 25 : Installation of sliding joint
top hat section steel sets
immediately
behind the face of a tunnel being
advanced through very poor quality
rock.

98. Figure 26 : Installation of 12 m long 75 mm diameter pipe forepoles in an 11 m span
tunnel top heading in a fault zone.

99. Figure 27 : Cables and shotcrete were used to support the roof of the
power cavern in the Mingtan Pumped Storage Project in Taiwan.

100. Figure 28 : Installation of cables in the sidewall of the power cavern in the
Mingtan Pumped Storage Project in Taiwan.

101. Figure 29 : Drilling machine for the installation of 40 m long reinforcing
cables in 50 mm diameter holes in a dam excavation.

102. Figure 30 : An example of good blasting in a tunnel.
A truck mounted shotcrete robot being used in a large civil engineering tunnel.
Note that the distance between the nozzle and the rock surface is approximately one metre.