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the embankment.

This insures complete drainage. Rain falling upon the
roadway will run off before it can penetrate the ground.

Provision must be made for conducting this surface water
into natural channels. This is accomplished by means of
side ditches.


1619. Ditching and Ballasting. All railroad man-
agers and operators are united in their estimate of the im-
portance of t/iorough drainage. This can be effected only
by a thorough system of drains and ditches. These should
be of such number and size that they will not only meet the
requirements of an ordinary rainfall, but also of the heaviest

Ditches are of two kinds, viz., side ditches, those excava-
ted in cuts on both sides of the roadway, and surface ditches,
those excavated above the slope of cuts to prevent the slope
from being washed down. Side ditches are partially made
during the grading of the roadway; surface ditches should
always be completed during construction, as they are of the
first importance in affording protection to the slopes against
the floods of surface water which invariably accompany a
heavy freshet. The water which, "during a heavy shower,
falls upon the side slopes and track, is about all that ordinary
side ditches can accommodate; and if the protection of sur-
face ditches is lacking, great quantities of surface water are


discharged at different points directly upon the unprotected
slopes, soaking the roadbed, carrying with it quantities of
earth and gravel which choke the side ditches, and, where the
quantity of water is sufficient, producing a washout. In fact,
the surface ditch- is indispensable to a newly constructed
road, and the question of its construction should not be open
to debate.

As stated above, the side ditches are partially made during
the grading of the roadway, and their completion deferred
until the ballasting and final surfacing of the track. All the
material excavated in completing the ditching should be used
in surfacing the track, and any additional material required
should be obtained by widening the cuts.

Wet, springy cuts are a serious annoyance and expense to
any railroad, especially where the widths of roadways and
slopes are limited by a fixed standard. A cut whose width
and slopes are ample for sand or gravel is totally inadequate
for clay. Springs in the bottom of the cut keep it constantly
wet, and a firm track is impossible. Frost and rain cause the
slopes to cave, filling up the ditches and often covering the
ties from sight. Such a track will be full of sags in summer
and badly heaved in winter, and at no time safe for trains at
high speed. There is nothing to be gained from tinkering
with and patching up such a track. The permanent cure
is in widening the cut and reducing the slopes, so that
whatever material caves in will lodge well outside the ditch
line. The ditches should be from 8 to 10 feet from the rails,
and so deep that the ballast will not be soaked by the water
flowing through them. The cost of such work will often be
heavy, but it will end the trouble and prevent the further
wasting of money in useless tinkering.

During the construction of the road, the slopes and width
ofroadivay should, so far as possible, be suited to the charac-
ter of the material in which the excavations are made.

The dotted lines in Fig. 508 show a standard section of a
through cut as made during the grading of the line, and the
full lines show the section after the track has been laid, the
cut widened, the ditches made, and the track ballasted. The


material excavated in this work is used for ballasting the
track. In establishing the grades for a new line, the com-
petent engineer will make provision for the drainage of the
cuts. Sometimes the grade is continuous throughout the
cut, carrying all the water one way; but where the average
grade is level, the drainage is effected by making the grade
to ascend from both ends of the cut, uniting them by an easy
vertical curve at the middle.

Where the cut is short, it is a mistake to break the gradient,
but rather depend for drainage upon well-constructed ditches.
Where the grade of the cut is level, the ditches at the middle
of the cut are made shallow, and the depth gradually in-
creased towards the ends. The grades of such ditches should

be given by the engineer, and the excavation made to con-
form to those grades. It is the continuous grade which
gives to a ditch its full efficiency. Where the grade is a suc-
session of levels and sudden drops, the level places accumu-
late mud on account of a sluggish current, and the steep
places wash badly because of a rapid current ; and in a
comparatively short time a new ditch must be made.

Particular attention should also be paid to the alinement
of the ditch. Crooks in the ditch impede the flow of the
water and tend to increase the deposit of mud. First
determine the line of the ditch, with a view of avoiding any
unnecessary excavation, and then cut the ditch to a true line.

When gravel or broken stone is used for ballast, the section
of the roadbed is somewhat altered, although its general
dimensions remain the same. As stated in Art. 16O3, the
ties should not be bedded when cinders, gravel, or stone



ballast is to be used. A section of roadway ballasted with
either cinders or gravel is shown in Fig. 509. The ballast is
filled in between the ties, flush with their tops, and extends
to a depth of 8 inches below them, sloping from the outer
top edge A of the tie to the edge of the ditch.

On some roads the shoulders at B and C are rounded off,
as shown by the line D , before the ballast is deposited.
The effect of this is to improve the drainage.

The ditch extends 12 inches in depth below subgrade;
i. e., the line B C.

The subgrade is the grade line laid down by the en-
gineers for the grading of the roadway, and marks the bot-

toms of cuts and the tops of embankments. The actual
%rade line marks the elevation of the top of the rail, and is
from 15 to 24 inches above subgrade. When gravel or
broken stone is used as ballast, the material excavated in
ditching the cuts should be loaded on a gravel train and de-
posited upon the embankments wherever needed. The more

FIG. 510.

material deposited on the embankments the better, as they
are bound to cave more or less from the effects of frost and
rain, before grass has grown in sufficient quantities to pro-
tect them.

A section of track ballasted with broken stone is shown in


Fig. 510. The ballast extends from 10 inches below the
bottom of the ties to the level of their tops, and is shouldered
outwards from the ends of the ties as shown in the figure.
The side ditches are 12 inches in depth, the slope of the bal-
last and that of the ditch forming practically a straight line.
The slopes of the cuts given in Fig. 510, as well as those
given in Figs. 508 and 509, are 1 horizontal to 1 vertical
This is the steepest slope at which earth will stand. The
certain effect of weather is to cause the slope to cave, flat-
tening it and at the same time filling up the ditches. In all
recent railroad construction, where the finances of the com-
pany will permit, the slopes of both cuts and embankments
are made the same, viz., 1| horizontal to 1 vertical. Cuts
can be widened much more cheaply before than after track-
laying, but it is often a difficult question to decide where it
is safest to economize.

The proper time to clean ditches is in the fall, commen-
cing about October 1 and finishing by or before November 1.
Occasionally the slopes of a cut cave in so badly that ditches
require frequent clearing. The only permanent cure is to
widen the cut to such an extent that caving material can not
encroach upon the ditches and track. Some writers on
track insist that there should be no side ditch nearer than
10 feet from the rails, nor slopes less than \\ horizontal
to 1 vertical. This would require a roadway at least
twenty-four feet in width for a single track, and involve
an outlay which would prohibit the building of nearly all
new lines.

The roadway and track sections given in the preceding
pages are entirely consistent with moderate expense and
thorough construction. When the line is fully equipped,
traffic connections established, and business on a paying
basis, there will be ample time for betterments and a pros-
pect of money with which to pay for them.

The purpose of all ditches and drains is to convey the
water to natural channels and thence out of reach of the
track. In Arts. 1461 and 1467, mention was made of
the common fault of making culvert openings too small.


They should be designed to meet the requirements of the
severest storms and freshets. At all low places where the
water remains standing alongside the track, open culverts
should be built, allowing the free passage of the water.
Brooks liable to overflow and wash the track should have
their channels deepened or their banks raised. After every
freshet, all water passages should be thoroughly examined
and all obstructions, such as sticks, brushwood, weeds,
etc., removed. Brush and weeds not only obstruct the
passage of water, but, when dry, are easily ignited by sparks
from the engine and are a continual menace to the safety of
the track.

Open passages for water, built of framed timber, are to be
condemned. They are likely to be undermined by a freshet,
and are at best a cause for anxiety. If stone is not avail-
able, the track should be carried on piles. The bents of
piles next the embankment should be sheathed up with plank
to prevent the washing of the embankment.

162O. Side Tracks. The opinion still prevails on
some roads that any kind of work or material will answer
for a side track. This is entirely wrong. The same skill,
work, and materials that go into the main track should be
expended upon all side tracks. The tax upon trainmen and
rolling stock is always greater on side tracks than on the
main line, and it is there that time is either saved or lost.
With a good track, shippers can move a loaded car with a
team ; whereas, if the track is rough, they are compelled to
wait for a freight train, which must stop until the car can
be shifted. It is admissible to use No. 2 ties in a side track,
except that all joint ties should be strictly first-class. Where
No. % 2 ties are used they should be placed closer together in
the track, so as to insure a first-class foundation for the
rails. All side tracks should, as far as possible, have a
switch at both ends. This permits trains to enter the side
track from both directions without passing a switch and
backing into the siding; it also effects a saving of time,
labor, and fuel.




1621. At the first break up of winter the spring track
work begins. The section foreman should plan his work so
as to take advantage of each day as the season advances.
As soon as the snow has disappeared from the track, which
will always be a few days earlier than from less exposed
places, he should set his men to work at cleaning up the
station grounds and yard. All scattering track material
should be collected and neatly piled at a place convenient to
the hand-car house. All rubbish which may have accumulated
during the winter must be removed and used either to fill up
low places in the right of way, or burned, if necessary.

All switches should be thoroughly repaired and put in per-
fect line. Battered rails should be replaced by good ones;
guard-rails and frogs examined and defects in them rem-
edied, and all ties collected, loaded on cars, and distributed
along the section, where they will be ready at hand when
needed to put in the track. All breaks in fences should be
repaired at the earliest opportunity. The approaches to
highway crossings should be made safe, and everything done
in the way of repairs which the season will permit of. As
the frost begins to leave the track, settlement commences,
and the track should be carefully watched, thick shims being
replaced by thinner ones as the settlement goes on, and all
shims removed as soon as it is possible to spike the rails to
their proper surface.

Every joint throughout the section should be examined;
all loose bolts tightened; nut-locks or washers supplied
where needed, and broken bolts replaced by new ones. As
the frost leaves the track, especially in wet cuts, soft places
will appear. These must be reported to the train dispatcher
at once. By keeping the side ditches clear and deepening
them as the frost leaves the ground, soft places can usually
be made safe until the ground settles, when thorough re-
pairs should be made. If the place becomes dangerous the fact


must be reported by telegraph to the roadmaster, who will fur-
nish the necessary men and materials to make the track safe.

1622. Washouts. The melting snow together with
the spring rains greatly increase the volume of surface
water, and as the frost comes out of the ground but slowly,
ditches and natural water channels are taxed to their utmost
capacity. It is at this season of the year that washouts and
landslides are chiefly to be feared. All ditches, culverts, and
bridges must be kept clear of obstructions, and the track
watched night and day so long as danger is to be appre-
hended. In case of a severe storm, the section foreman
should send a responsible man to one end of the section with
the proper signals to stop trains in case of danger, while he
goes to the other end of the section, leaving a man to guard
any dangerous spot until the section is entirely covered. In
case he lacks the means to repair any damage done, he must
report the fact by telegraph to both the train dispatcher and
roadmaster, in order that the former may hold trains at
convenient points while the latter can rush a construction
train through to the point of danger. The foreman should
include in his report the location of the break or washout,
the number of the bridge or culvert, the length of the break,
the number of missing bents, and any information which
will aid the roadmaster in making a correct estimate of the
men and materials necessary to repair the damage. He can
then set to work with his men, making such repairs as his
limited force will permit of, and being ready to render every
assistance in his power to the roadmaster, who assumes
charge on his arrival. A foreman should never attempt any
repairs of track until he has inspected his entire section, as
two or more breaks may occur simultaneously, and while re-
pairing one break an accident is liable to occur at another.

1623. Repairs of Track. As soon as the frost has
left the track and all shims have been removed, bringing
the rails down to the surface of the ties, the section foreman
should go rapidly over his section, making such repairs as
will render the track safe and reasonably smooth. If the


track is well ballasted with gravel or broken stone these re-
pairs will be quickly made, as such track will hold a good
line and surface after the severest winter. If, however, the
ballast is clay, the track will show many low places and an
uneven line. The track jack, shovels, and picks are all the
tools needed for the first repairs. A man is set to dig block
holes for the jack at the lowest points in the sags. The
track is then raised until it is in average surface with the
track at either end of the sag. Dirt is then shoveled under
the ties, care being taken to throw it well back to the middle
of the tie. No attempt should be made to tamp the ties other
than to fill up the cavities formed by raising them. A part
of the force will follow, dressing up the track and filling
block holes. The foreman should stop raising track about two
hours before quitting time, taking with him sufficient hands
to line up and gauge the track surfaced during the day.
The line side of the track is then given a perfect line.
Either rail may be taken as the line side, but the same rail
should always be used for lining. A part of the force take
the gauge and spike maul and spike the track to gauge,
while the rest follow, dressing up the track. This work will
put the track in perfect line and fair surface, and by the time
the entire section is covered the ground will be thoroughly
settled and the track in shape for permanent surfacing.

1624. Lining Track. When lining track the fore-
man should stand with his back to the sun and as far from
the piece of track which he is to line up as -his eyesight will
permit. This gives him a better view of the straight
portions on each side of the crooked portion, all three of
which are to be brought into the same straight line. A
simple device, much practiced by trackmen when lining
track, is to place small lumps of dirt on the top of the rail
to be straightened. These lumps show plainly in contrast
to the bright, unbroken surface -of the rail, and when
brought into range insure a good line.

With a strong section gang the foreman can readily per-
form any of the tasks which confront him ; but when from


necessity his force is reduced to a minimum, he is obliged to
resort to every expedient within his knowledge. He must
not only direct the work, but lead in its execution. Fre-
quently a foreman will have charge of ten miles of track,
and have but four hands besides himself wherewith to main-
tain it. It is under such circumstances that ingenuity and
energy count at their full value.

When a sag in the track has caused a crook in the line, and
there is not sufficient force to throw the track to line, the
following scheme will enable the foreman to straighten the
track and hold it in place. He can only straighten one rail
length at a time, and to do that he should remove the spikes
from three or four of the ties under the rail. The ties so
detached from the rail are called dead ties. The lining
bars are then placed under the rail upon the dead ties, which
afford a far firmer foundation and leverage than ordinary
ground. The track is then thrown to line, after which the
dead ties are shifted to their proper position. If the track
has a tendency to slip back out of the line, the rails can be
temporarily spiked to the dead ties, which, being securely
bedded, will hold the rails permanently in place.

1625. Straining of Track Bolts. Reference has
already been made to this serious fault, which is almost
universal among trackmen and generally due to ignorance
on their part. The rail splices on most American roads are
fitted with nut locks of either metal or fiber, the object of
which is to lock the nut and at the same time permit of the
expansion and contraction of the rail. In order that expan-
sion and contraction may take place, the nut should only be
brought to a snug bearing on the nut-lock, whereas, the
common practice is to screw on the nuts as far as the strength
of the trackman will permit. This places the bolt, nut-lock,
and nut under a severe strain, with the result that the rail
can not freely expand and contract; the nut-lock is deprived
of -all power to act, and at the first abrupt change of tem-
perature the nuts are liable to snap off on account of the
sudden strain. One of the first duties of the section fore-
man is to explain to his men the object of the slots in the


rails, expansion shims, and nut-locks. In putting in track
bolts, first bring the nut to a bearing, after which a half
turn with the wrench is sufficient. Track wrenches should
not be longer than 16 inches for f-inch bolts. Spike slots
should always be made in the angle splice. These prevent
the creeping of the rails and at the same time permit the
free expansion and contraction of the rails.

1628. Removing Old Track Bolts. In removing
old track bolts they should never be battered with either
hammer or wrench. The nut should not be entirely re-
moved from the bolt until the bolt is loosened in the
splice. When the nut is nearly off the bolt, give it a
slight tap with the track wrench. This will loosen the bolt
without injuring the thread. The thread of the old bolts
should be oiled and the nuts well screwed on so that they
will be complete and in readiness for service when needed.

1627. Loose Track Bolts. Changes of temperature
often cause the loosening of track bolts. These are most
noticeable in the spring and fall of the year. Trackmen
should watch for and promptly tighten all loose track bolts,
as they are one of the main causes of low joints.

1628. Line and Surface of Bridge Approaches.

Special care should be taken to make the line and surface
of the track on bridge approaches as nearly perfect as pos-
sible. Pile bridges are liable to heave, especially when the
ice surrounding them is lifted by a spring freshet. Section
men should not attempt to repair bridges unless circum-
stances require it. They have neither the experience nor
tools for such work.

Bank sills (those resting upon the embankment and
supporting bridge stringers) are continually settling, and
cause a bump, or lift, in the track at the bridge line. The
sills should be raised and kept in perfect surface by hard
tamping, and all bank ties kept well tamped. If possible,
avoid placing a rail joint over a bank sill. It is almost cer-
tain to be low at times ; but rather arrange the track so as
to bring the center of the rail at that point.



1629. General Repairs. On Northern railroads,
general track work commences with the month of May. By
that time all frost has left the track and settlement has
taken place generally.

The section foreman should go to the end of his section
to commence track repairs, and work towards home, finish-
ing as he goes, raising all small sags and low joints to
a proper surface, tightening all loose bolts, relining the
track, and correcting all defects in gauge. He should fill
in the middle of the track and dress it down to the track
shoulder. He should allow nothing short of actual com-
pulsion to call him from his work until the entire section
is covered. He will then be in readiness to put in new
ties, lay new steel, surface track, or cut weeds according
as the work demands. In going over the track, the fore-
man can correctly estimate the number of new ties needed
and make early requisition for them in order that they
may be on hand when needed. He should keep a record
of the places where new ties are needed and distribute them

1630. Track Ties. Track ties constitute one of the
most important items in the initial cost and maintenance of
a railroad. The company should provide the best ties
within their means, and, if possible, have them well seasoned
before being placed in the track. Ties made from logs split
in two parts should be laid with the sap side up. This
brings the wide or heart side of the tie underneath, which
is the position it would naturally take. Pole ties, those
made from young trees, are more lasting than those made
from large logs, as the older the tree, the more open and
brittle the timber. Sawed ties are usually smaller than
hewn ties. They are also often cross-grained, and hence
more easily broken. Tie specifications should always
require uniformity in length and thickness and the removal
of all bark. Tie inspectors should strictly enforce these
specifications. Tie contractors are quick to note any


laxness in the enforcement of specifications and always ready
to take advantage of it.

Ties in the roadbed should be not less than 8 feet in
length, 7 inches in thickness, and show at least 7 inches of
face and be hewn to a uniform thickness throughout their
entire length. Winding ties should be promptly rejected.
They are dear as a gift.

The life of a tie depends not only upon the kind and
quality of its timber, but also upon the weight of the rails,
condition of the roadbed, and much upon the climate. In
Northern latitudes, decay is almost entirely suspended dur-
ing the late fall and winter months, while in Southern
latitudes decay goes on almost uninterruptedly throughout
the year. The yellow pine ties of the South are best fitted
to withstand the effects of the climate, and when of sound
heart timber they are fairly lasting.

The loss sustained from the use of inferior ties is apparent
when one considers the cost of repairs and renewals. A
track laid on ties with an average life of 8 years, and cost-
ing 60 cents each, is vastly more economical than a track

Online LibraryInternational Correspondence SchoolsThe elements of railroad engineering (Volume 2) → online text (page 31 of 35)