Page images
PDF
EPUB

TABLE II—CONCLUDED

[graphic]

Maple-silver Acer saccharinum
Sassafras Sassafras sassafras
Cypress-bald Taxodium

distichum Douglas fir, Pseudotsuga

mountain taxifolia
Chestnut Castanea dentata
Pine-jack Pinus divaricata
Pine-lodgepole Pinus contorta
Hemlock-eastern Tsuga canadensis
Pine-western

yellow Pinus ponderosa
Cottonwood Populus deltoides
Poplar-yellow Liriodendron
or tulip tulipifera
Catalpa Catalpa catalpa
Butternut Juglans cinerea
Spruce-white Picea canadensis
Redwood Sequoia

sempervirens
Cottonwood- Populus
black

trichocarpa
Cedar-western
red

Thuja plicata
Cedar-white Thuja occidentalis

.31
29

310
290

5200
4200

52
48

37
35

63
51

1

TABLE III-UNTREATED TIE SERVICE-100=8 Years

Decay Failures

Mechanical Failures

Failures Partly Decay and Partly

Mechanical

Relative
Life of Ties

Per
Cent Years

Climatic Climatic Climatic

Climatic Climatic Climatic
Conditions Conditions Conditions

Conditions Conditions Conditions
Such That | Such That Such That

Such That Such That Such That
Under Light Under Light Under Light Traffic Conditions Such That Failures of White Under Light Under Light Under Light
Traffic, Traffic, Traffic,

Oak Are All Mechanical in

Traffic, Traffic, Traffic,
White Oak White Oak White Oak

White Oak White Oak White Oak
Ties Fail by Ties Fail by Ties Fail by

Ties Fail by Ties Fail by Ties Fail by
Decay in Decay in Decay in

Decay in Decay in Decay in
6 Years 8 Years 10 Years 4 Years 5 Years 6 Years 7 Years 8 Years 9 Years 6 Years

8 Years 10 Years (1) (2) (3)

(5)
(7) (8) (9) 10)

12)
150
200

250

55 69 83 96 110 124

103 128

153 112 150

188

25
31
38
44
50
56
69
88

107
140

175

43 53 64 74 85 96 74 92

109 130

163

30 38 45 53 60 68

64 80

97

[ocr errors]
[ocr errors]

(11 (12

)

250
200
188
175
163
150

20
16
15
14
13.1
12.0

105

98

90
90
83
75

120
120
110
100

150
150
138
125

45
35
34
50

56
44
42
63

68
53
50
75

79
61
59
88

90
70
67
100

101
79
75
113

68
63
59
63

83
78
72
75

98
93
86
88

120
110
100
95

9.6
8.8
8.0
7.6

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small]

Kind of Wood

Untreated

Black Locust
Cedar
Walnut
Redwood
Heart Pine

(Compact Wood
Cypress
Chestnut
White Oak
Douglas Fir

(Coast)
Larch (Tamarack
Ash
Sap Pine
(Compact Wood
Beech.
Elm
Birches
Hemlock
Gums
Red Oak
Maples
Sap Pine

(Coarse Wood).
Sycamore
Honey Locust
Butternut

30
26
23

40
35
30
25

50
44
38
31

SS
39
50
30

19
68
75
45

57
67
88
59

65
77
100
60

73
87
118
68

32
33
37
25

37
$7
40
28

35
30
25
20

2.8
2.4
2.0
1.6

63
38

19

[ocr errors]

Italics indicate cases where decay rather than mechanical destruction may determine the life of the tie under the climatic conditions indicated in columns 1, 2 or 3.

This table has been prepared under the assumption that the mechanical life of a tie is proportional to its mechanical strength, as indicated by ito specific gravity, and that the relative resistance of various woods to decay is independent of climate. Tio platos aro assumed, when required, in accordance with serato practice. This assumption of tie plates is intended to care for the situation where a hardwood tie lails by decay and under the same conditions a soft wood tie, unplated, would fail mechanically. It is recognized that this assumption would not always hold good,

[graphic][ocr errors][merged small][merged small][subsumed][subsumed][ocr errors][subsumed][ocr errors][merged small][ocr errors][ocr errors][ocr errors][subsumed][ocr errors][subsumed][merged small][merged small][subsumed][subsumed][subsumed][subsumed][subsumed][merged small][subsumed][merged small][merged small][subsumed][merged small][merged small][merged small]
[graphic][subsumed][ocr errors][ocr errors][subsumed][subsumed][subsumed][ocr errors][ocr errors][ocr errors][merged small][subsumed][ocr errors][subsumed][subsumed][ocr errors][subsumed][subsumed][subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed][ocr errors][ocr errors][subsumed][subsumed][merged small][merged small][merged small]
[graphic][merged small][subsumed][subsumed][subsumed][subsumed][ocr errors][merged small][subsumed][ocr errors][merged small][subsumed][subsumed][subsumed][subsumed][subsumed][merged small][merged small][merged small][merged small][merged small][merged small]
« PreviousContinue »