III. Recognition of avalanche risk
V. Structures for deviating, braking and containing avalanches
VI. Structures for stabilizing snow in the avalanche starting zone
VII. Wind deflecting structures
X. Terminology and symbols used
Chapter II
1, 2 Examples of maps of average extreme heights of
snow
3 Distribution of velocities in the profile of
the snow cover
4a), 4b) and 4c) Different shapes of starting, transit
and arrest zones
Chapter III
5 Avalanche report card
6 Code for identifying various types of avalanches
7 Distribution of old and new houses in Neustift
8 Map for localizing likely avalanches
9 Yap of areas exposed to avalanches
10 Speed profile in an avalanche simulation experiment
in a channel submerged in water
11 Plan of a wedge-shaped house
Chapter IV
12 Graph of a snowfall period for continual assessment
of avalanche danger
13 Relation between incident and reflected pressure
for normal reflection on a rigid surface and on the surface of the snow cover
14 Pressure wave caused by an explosion above the
snow cover as a function of the height of the explosion and the distance from
point zero
15 Pressure wave for an explosion above the surface
of the snow
16 Sketch of a remote control release system
Chapter V
17 Layout of braking structures and retaining dam
18 Readings from the roofs of galleries
19 Length of the measuring device placed on the roof
of a gallery
20 Static and dynamic loads on a gallery; deviating
forces against a deviating wall, and a wedge or spur
21 Forces exerted on a gallery by static and dynamic
loads
22 Site plan for a deviating structure
Chapter VI
23 Specifications for old berms and stakes
24 Extra load on an inclined superstructure
25 Distribution of the pressure of snow on a support
surface of limited width
26 Influence of a snow stabilizing structure on the
shear stress manifested at ground level
27 The marginal factor f R as a function of snow glide
and the spacing between structures
28 Extra marginal load S'R on the exposed
side of a structure and on one within a defence system
29 Resultant snow pressure
30 Application of the resultant load and distribution
of snow pressures for the two fundamental examples of loading
31 Load P' perpendicular to the superstructure
32 Cross section of the pressure of snow
33 Plan view of the pressure of snow
34 Determination of the effective load-bearing width
of a cross-beam of a superstructure
35 Load Q´ parallel to the superstructure
36 Direction and loads on a cross-beam of the forces
acting perpendicular and tangentially to the superstructure
37 Separate foundation bases (sketch of the forces)
38 Foundation bases joined by a tie-bar
39 Admissible compression of the ground and direction
of the load
40 Temporary snow rake made of wood
41 Sealed foundations. Compression of the ground by
the upper foundation base
42 Sealed foundations. Extraction force on the upper
foundation base
43 Sunken foundations. Compression of the ground by
the upper foundation base
44 Sunken foundations. Extraction force on the upper
foundation base
45 Foundation base anchored in rock
46 Sketch of the principles of compression tests
47 Compression test
48a), 48b), 48c) and 48d) Examples of the layout
of structures
49 Rigid superstructures; slack superstructure, net
50 Spacing factor f L
51 Determination of gap in staggered structures
52 Staggered layout must respect the normal spacing
L
53 The length of structure 1 in a discontinuous layout
54 The length in a staggered layout
55 The length in a combined layout
56 Cost/safety ratio
57 Formation of a ramp over a snow stabilizing structure
58 Number of linear meters of stabilizing structures
per hectare in a continuous layout
59 Example of a 1:500 map of a defence area
60 Complete control of a portion of terrain
61 Partial control of a portion of terrain
62 Cost of structures as a function of D K
63 SFISAR snow rake made of round timbers
64 Details of the SFISAR snow rake
65 Admissible anchorage loads for half a 4 m. structure
66 Manner of execution of nailed joints for round
timber snow rakes
67 Horizontal spacing in meters
Chapter VII
68 Examples of profiles of snow deposited in the shelter of wind baffles
Chapter X
69 Snow bridge, snow rake, net
Chapter VI
1 Admissible loads for wood
2 Advantages and drawbacks of the three types of
layout
3 Spacing of structures along the line of steepest gradient
according to Fig. 50
4 Types of ground and glide factor N
5 Table of spacing L to be used as a function of slope
angle and normal thickness of snow cover DK
1 High up in an area of defences, with the upper terminal of a works cable-way
Chapter III
2 Medium altitude avalanche zone
3 Example of a surprise attack: a chalet too near to
the red zone has finally been hit
4 Snow covered basin high in the Rocky Mountains
5 Turf torn away; cow trails
6 Natural catchment area and beginning of transit zone
(looking down)
7 This avalanche recurs every spring
8 An avalanche cone. Upper right: the end of the transit
zone
9 Simulation of an airborne powder avalanche
10 One splitting-wedge protects the whole village
Chapter IV
11 Attempt at blasting a cornice
12 Lighting a home-made explosive charge
Chapter V
13 Deviating dam built at the beginning of the seventeenth
century at Loéche-les-Bains
14 Staggered deviating walls to prevent avalanches
leaving the gulley
15 Earth dams to canalize an avalanche
16 Old protecting wedge behind a mountain-pasture
chalet
17 Braking structure in the shape of a truncated cone
18 Braking structures in the shape of stone-filled
wire baskets
19 Multi-functional braking structure in a gulley
20 Containing structure. Earth barrier
21 Protective gallery over a railway line
Chapter VI
22 Snow rakes and rows of stakes after Coaz
23 Evolution of the wall: free-standing wall
24 Wall filled in on the uphill side
25 Wall heightened by a structure made of turf
26 Walled terrace heightened with a vertical wooden
snow bridge
27 Final evolutionary stage of the walled terrace
- for when snow reaches a height of five to six metres
28 Snow bridge made of old railway track and round
timbers
29 Snow bridges made of steel and chestnut-wood sections
30 Snow bridge made of pre-stressed concrete
31 Snow bridge made of aluminium alloy
32 Steel snow bridge
33 Steel snow bridge which is adaptable to the terrain
by means of telescopic supporting pillars
34 Snow rake made of chestnut-wood
35 Snow rake made of wood and steel
36, 37 Snow rakes made of steel and wood
38 Net made of steel cable
39 Net made of plastic material
40 Nets stand up remarkably well to stone falls
41 Compression test
42, 43 and 44 Examples of the layout of structures
45 Partial collapse of structures caused by overloading
46 Consequences of the collapse of an upper structure
47, 48 and 49 Overloaded defences during spring
50 Winter view of a controlled area (discontinuous
layout)
51 Summer view of this area
52 Works cable-way
53, 54 Building a works' access road
55 to 64 Assembly of a snow rake made of round impregnated
timbers
65 Crevasse due to snow creep and glide at the beginning
of winter
66 Up until spring, snow creep and glide can, in places,
assume considerable proportions
67 Plantations flattened by snow creep and glide
68 Net supporting pillar bent by snow creep and glide
69, 70 and 71 Practical examples of small berms or
terraces to combat snow creep and glide
72 Anti-creep and glide structure (rows of stakes)
73 Old anti-creep and glide rakes
74, 75 Anti-creep and glide structures (bridges and
rakes)
Chapter VII
76 Remodelling of the snow cover by the wind
77 Snow cornice
78 Dry-stone wind baffle
79, 80 and 81 Different types of wind baffle (made
of planks)
82, 83 and 84 Different types of eddy panels
85 Road protected by a mixed complex of defences
Chapter VIII
86 Staggered wall-dams protecting the entrance of
a tunnel
87 Wall-dams protecting a village
88 The practical effect of a wall-dam
89 Braking structure at the opening of a deep valley
90 Mixed defence complex
91 An area with complementary defence structures
92 Structure to contain an avalanche
93, 94 Tunnel-cum-gallery through an alluvial cone
95 Avalanche spreading out over a gallery (problem
of lateral over-flow)
96 Detail of an old splitting-wedge behind a chalet
97 Modern wedge to protect a building
98 Snow bridge reinforced on its exposed side by a
separating wall
99 Effect of the separating wall
100 Braking structures with a containing dam
101 Deviating wall which protects an area of snow
bridges
102 Extension of an old area of defences consisting
of banked-up walls with steel snow bridges
103 Protection of an area of terrain
104 Snow bridges of mixed materials (frames of durable
material with superstructures of wood)
105 Efficacy of a snow rake during winter
106 to 109 Details of the anchorage of a steel snow
bridge to rock
110, 111 Examples of defence works combined with
reforestation
112 Layout of wind baffles made of wooden, non-adjoining
planks
113 Efficacy of a wind baffle
114 Detail of the deposition of snow produced by
a wind baffle made of vertical planks with small gaps between them
115 Detail of the deposition of snow produced by
a wooden wind baffle with no gaps
116 Wind baffle to combat snow drifts
117, 118 Light galleries to combat snow drifts
119 Effect on the snow of a complex of eddy panels
120 Use of eddy panels to reduce the load on an area
of snow bridges
121 Detail of the construction of a wind baffle;
girder and raking shore made of steel
122 Effects on the snow of a complex of jet-roofs
123 to 126 Examples of damage caused by poor foundations
127 Example of damage caused by bad workmanship
128 Steel-cable stays are not recommended when they
have to be taut in the snow cover
129, 130 and 131 Examples of damage caused by falling
stones
132, 133 Structures ill-adapted to the pressure of
snow
134 Deformation of a snow bridge due to excess pressure
on its exposed side
135 Partial collapse of an old terrace
136 The essential condition for reconstituting forests:
a separation of forest from pasture
