Traffic rail, lb per yd
Guard rail, lb per yd
130
100
100
85
85
70
75
60
4.10.
SUMMARY
Guard rails are placed between the running rails to catch derailed wheels, thereby preventing equipment
from overturning or leaving the ties. They are used most frequently on bridges and at tunnel entrances. Because
guard rails complicate maintenance, they should not be used unless absolutely necessary. They should never be
larger in section than their adjacent traffic rails.
Section III. Seasonal Problems
4.11.
GENERAL
Many serious maintenance problems affect railroads only seasonally. Winter and summer provide violent
extremes of weather which often damage the right of way and track structures. The first two paragraphs of this
section cover the main summer maintenance problems and their solutions. Most of the remaining paragraphs
cover the problems encountered in the winter in cold climates and their solutions. The last paragraph explains
how to preserve the safety and comfort of the maintenance gang in cold climates during the winter.
4.12.
WEED GROWTH
Probably the most obvious result of summer weather is a great increase in plant growth. Weeds of all
varieties burst forth in an apparent attempt to completely conceal the railroad right of way. Given the chance,
weeds will overrun seldom used tracks, fill drainage ditches, and create an unsightly condition.
Weeds growing in the roadbed hold water, contaminate ballast, and cut off drainage. Ties then become
rotted, and line and surface are lost. Figure 4.3 illustrates excessive growth of weeds in track; figure 4.4 shows
the effect of such growth after the weeds are removed; and figure 4.5 is an example of good weed control. These
pictures show why it is essential to fight weed growth before it gets a good start. It is not necessary to explain
here the danger of
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