International Correspondence Schools.

The elements of railroad engineering (Volume 2) online

. (page 29 of 35)
Online LibraryInternational Correspondence SchoolsThe elements of railroad engineering (Volume 2) → online text (page 29 of 35)
Font size
QR-code for this ebook

material is classified, the foregoing methods of computing
areas can not be employed except to check the aggregate
area, and when the slopes vary with the different materials
other methods must be entirely used.

Where there is no indication of rock, the slope stakes are
set to the usual slope of 1 horizontal to 1 vertical. If rock
is encountered before the rock excavation is commenced,
the slope is contracted to ^ horizontal to 1 vertical.

It has been customary to plat irregular sections on cross
section paper. The original or surface cross-sections are
first platted, and when the top material (usually earth) has
been removed, a cross-section of the remaining material is
taken and platted on the original sheet, the lines being



drawn in colored ink. If there is still another classification
of material, as shown in Fig. 487, a final cross-section is
taken and platted in lines of a separate color.

The different colored lines at once indicate the outlines of
the various materials and assist in checking the calculations
of the partial areas. The original cross-sections and the fin-
ished section should be in black, the others in distinct, sep-
arate colors.

The partial areas are easiest calculated by dividing -them
into triangles and carefully scaling all dimensions not

Cut 5'

FIG. 487.

In Fig. 487 we have, remembering that the slopes of f g
and c h are 1 to 1 :

9x2 = 18.0 sq. ft.

9x1 = 9.0 sq. ft.

11X2.1 = C3.1 sq.ft.

10x2.1 =21.0 sq.ft.

18.0 sq.ft.

Area of triangle a b c of solid rock =
Area of triangle b e foi loose rock =
Area of triangle b e k of loose rock =
Area of triangle c b k of loose rock =
Area of triangle c d k of loose rock =18.2x1.15= 15.2 sq. ft. 68.3sq. ft.
Area of triangle de g of earth =27.2x1.65= 44.88 sq. ft.
Area of triangle dg h of earth =34. X2.2=74.8 sq. ft. 119.7 sq. ft.
Total area of section 206.0 sq. ft.

159O. Quantity Books. Quantity books spoken of
in Art. 1588 are of various forms. The following is rec-
ommended. It contains station and cross-section notes of
Fig. 487, together with the end areas:


























3 S

o -

H <J



T3 4,5

"^ o












o 9


W5 ^










r-H i-H


uop E ;s



This form of notes includes both left and right-hand pages
of the book, and the classification of material meets the re-
quirements of most railroad work. When the material in-
cluded between two consecutive cross-sections is of the same
character, the prismoidal formula should be used in calcu-
lating the cubical contents of the included prismoid, but
when the sections are classified, as in Fig. 487, the mean
area of each material shown in both sections should be taken
and multiplied by the distance between the sections. When
one kind of material, such as rock, shows in one section and
not in the next following, the point where that particular
material ends should be determined and the distance from it
to the section containing rock should be measured. This
mass of rock will be considered either as a pyramid or a
wedge, according to its form. When of wedge form, its vol-
ume is the product of its base by one-half its altitude or
length, and when of pyramid form its volume is the product
of its base by one-third its altitude or length.

The partial and total areas of each section are placed on
the same line under their proper headings. As the number
of the station at which each cross-section is taken is given
in the station column, the distance between any two sec-
tions is readily found by subtraction. The quantities are
carried out on the same line as the end areas and placed
under their proper headings. Thus, in calculating the ma-
terial between Sta. 50 and Sta. 50 -f- 50, place the quanti-
ties on the Sta. 50 -\- 50 line, which is next below Station 50.
When a page of the quantity book is filled, add the several
columns of quantities which are given in cubic feet, and re-
duce them to cubic yards by dividing by 27. At the end of
each mile section a blank page should be left in the quantity
book. A summary of the total yardage of each kind of ma-
terial handled in the grading of the section is then made out
and placed on this blank page, together with the contract
price and. value of the work. Wherever a trestle or cul-
vert occurs, a space should be left in the quantity book at
the proper station, large enough to contain a sketch and
estimate of the materials for the same. Spaces should also


be left for borrow pits and any special excavation. All
these partial estimates will appear in the summary in proper
order. The following will serve for a guide:




Earth 10,000 cubic yards @ 20c $2,000.00

Loose rock 1,500 cubic yards 40c 600.00

Solid rock 850 cubic yards @ 80c 680.00

Borrow 2,000 cubic yards @ 20c 400.00


First-class .... 190 cubic yards $10.00 $1,900.00

Second-class... 220 cubic yards @ 6.00 1,320.00

Rubble 270 cubic yards 4.00 1,080.00

Rip-rap 300 cubic yards @ 60c 180.00

Paving 120 sq. yd. @ 90c 108.00


4,000 lineal feet @ 30c $1,200.00

Trestle Timber.

100,000 feet board measure, in work @ $30 $3,000.00


3,000 pounds @ 4c $120.00

Total cost of grading, masonry, and trestling on

Section 10 $12,588.00

.1591. Monthly Estimates. On or about the last
day of every month during the progress of construction,
measurements are taken to determine the total amount of
work done and materials furnished up to that date. It is
frequently necessary to take measurements for both monthly
and final estimates at other times than the closing days of
the month. This is especially the case in foundation work
where the masonry is started as soon as the excavations are
completed. When the roadway has been completed, the


monthly and final estimate will be the same. The quanti-
ties are taken directly from the quantity book, where end
areas of sections and volumes are carefully calculated and
carried out in regular columns.

An approximate estimate is made of all work in progress,
care being taken to make it as exact as the nature of the
work will allow.

A special field book is used for monthly estimates, in
which a description is given of the particular work or struc-
ture measured, together with the date of measurement. The
notes consist principally of the cross-sections of incompleted
roadway. Wherever the roadway is completed to grade,
the word " completed " is commonly written opposite the
station and the quantities computed from the original cross-
sections. Notes of foundation pits are made doubly clear
by a sketch of the excavation with dimensions marked on
the outlines. All special work, concerning which a misun-
derstanding may possibly arise, must be particularly

Materials, such as lumber, stone, etc., furnished by the
contractor and not put into any structure at the time the
estimate is taken, should be measured and the amounts
placed under the head of temporary allowances, the price
allowed being somewhat less than the actual value of the
material as delivered.

Blank forms are used by the resident engineer in reporting
monthly estimates. In these forms a column is provided for
each of the different classes of material and work contained
in the contract. The stations are numbered in the first col
umn in regular order, and opposite each station in the
proper column the amount of excavation, masonry etc., is

An estimate is made for each particular mile section into
which the line of railroad is divided for letting.

The resident engineer should keep, in a separate book, a
record of each monthly estimate.

The monthly estimates are forwarded to the division en-
gineer, who reviews them, copying the footings of the several


columns into a separate book in which the sections of his di-
vision are placed in regular order. The prices are affixed to
the quantities and the total amounts carried out. From the
totals, the amounts of previous estimates are deducted, and
the remainder is the amount due the contractor for the
month. From this amount a certain percentage (usually 15
per cent.) is deducted to be reserved by the company until
the completion of the contract.

A summary of the monthly estimate is then forwarded by
the division engineer to the chief engineer for auditing and

1592. The Final Estimate. The final estimate is
a complete statement in detail of the amount of work done
and the materials furnished in the construction of the road,
and is the basis of final settlement between the company and
the contractor. It should be commenced as soon as con-
struction is under way and continued as fast as the necessary
data may be collected.

Full notes must be kept of each particular structure and
complete measurements taken while the work is under way
and the circumstances fresh in mind. This is particularly
important in the case of bridge and culvert foundations and
other structures, either under water or covered with earth at
the completion of the work. These sketches and notes will
be recorded at their proper station in the quantity book
described in Art. 1 59O. When the work is completed, a
final summary is made containing the aggregate quantities
of the entire line.

Full notes are kept of all classified materials and of all
material affected by length of haul (providing a haul clause
occurs in the contract) and arranged in the order in which
the work occurs on the line.

The calculations for final estimate limit the monthly^
estimates and guide the engineer in making approximate
estimates of either work or material.



1593. There is no department of modern railroad
engineering which is receiving so much attention as the
care and maintenance of the track. In the great strife for
business, freight and passenger rates have been reduced to
a minimum, and to meet these conditions speed and train
loads have been nearly doubled. These conditions demand
a good track.

A track to be good must be laid on sound ties, well
ballasted and surfaced, full spiked and bolted, and in perfect
line and surface.

1594. New Road. In America practically all newly
constructed railroad is built of new material throughout,
though the cross-ties are often cheap and the rails light.


1595. Cross-ties are of wood. Their size and variety
of timber will depend upon the locality and financial ability
of the railroad company. The best ties are of white oak.

The following list gives in a descending scale the com-
parative values of woods for cross-ties:

Hard Wood. Soft Wood.

White Oak. Red Cedar.

Rock Oak. Black Cypress.

Burr Oak. White Cedar.

Chestnut. White Cypress.

Southern Pine. Tamarack.

Walnut. Butternut.

Cherry. White Pine.

Red Beech. Hemlock.

Red Oak. Spruce.


It is generally accepted that hewn ties are superior to
sawed ties. The surface of a well-hewn tie is a series of
comparatively smooth surfaces. The effect of the ax is to
close the pores as the chip is removed, which tends to exclude
the moisture. The effect of the saw is exactly the reverse
of the ax. While given an average smoother surface, it
tears the fiber of the wood, leaving the pores open. These
minute broken fibers which cover the entire surface of the
tie act like sponges in attracting and retaining moisture,
and eventually hasten decay.

1596. Importance of Seasoning. Too little atten-
tion is paid to the seasoning of cross-ties before they are
laid in the track. This is especially true on newly con-
structed lines where scarcity of capital and the necessity for
keeping down expenses compel the use of the cheapest
material and methods. Cross-ties thoroughly seasoned will
last fully one-quarter longer than those used while green,
and they are better in every way. Well-seasoned wood will
hold the spikes better and resist the shearing tendency of

the rails due to passing
loads better than green
ties. The most favorable
months in Northern lati-
tudes for cutting ties are
August, December, Janu-
ai T> and Febr uary. Dur-

FIG. 488. ing these months there is

comparatively no movement in the sap of the trees. The
ties should be hewn to uniform thickness and piled in square
piles about 4 feet in height, as shown in Fig. 488, so as to
admit of the free circulation of the air and to hasten the
seasoning process.

1 597. Specifications for and Inspection of
Cross-Ties. Specifications should include dimensions, and
kind and quality of timber. Ties for standard gauge tracks
should be from 8 to 9 feet in length, from 6 to 8 inches in
thickness, and show not less than 6 inches of face. The


standard tie is 8 feet 6 inches in length, 7 inches in thick-
ness, and shows at least 7 inches of face. In the Northern,
Middle, and Western States, log ties, i. e., ties cut from
entire trees and showing two rounded sides, are principally
used. In the Southern, Atlantic, and Gulf States, yellow
pine ties are in almost universal use. They are square hewn
and made of heart timber, not more than 1 inch of sap being
allowed on the corners. In Southern latitudes, where the
process of decay goes on throughout the year, sap timber is
almost worthless. The sap timber soon softens, the spikes
loosen and the rails cut into the wood, leaving the track in
a dangerous state. In those portions of the South where
oak is abundant, oak ties are much used. They are generally
square hewn. This is a mistake, especially if the ties are
cut from young thrifty trees (and no other timber should be
used), since a considerable portion of the weight of the tie
is sacrificed in squaring. This lost weight is all needed to
give stability to the track. The ties should be cut off square
and to uniform lengths, and be of a uniform thickness
throughout their entire lengths. Before being inspected,
they should be delivered along the right-of-way of the rail-
road and piled in regular piles, each tie showing both ends.
Ties are commonly graded as firsts and seconds. The in-
spector carries a brush and pot of paint, marking each class
of ties with a distinctive mark. Firsts are usually marked
by a full circle, and seconds by a cross.


1 598. It is a rare thing to find a new roadbed in proper
condition for track laying. Often it is in poor surface, being
left by the contractors in a rough, uneven state. If the track
is being laid in heavy, wet weather and the ties are being
distributed by teams, the wheels are sure to cut deeply into
the roadbed, and unless some precaution is taken to bring
the tops of the ties to a uniform surface, there is great
danger of the rails being bent by the passage of the
construction train.


1599. Track Centers. Center stakes marking the
alinement are driven at intervals of 100 ft. on tangents and
50 ft. on curves, where the degree of curve does not exceed
12. On curves exceeding 12, stakes should be driven at
intervals of 25 ft. A tack is driven in each stake, marking
the center of the track. Grade stakes for surfacing ties
should be placed at intervals of 16 ft. A straight edge
placed upon these stakes marks the grade for the inter-
vening ties. The ties are bedded with earth taken from
the roadbed and tamped with the shovel.

The placing of grade stakes so close together is contrary
to common practice, but the increased labor for the engineer
is more than compensated for by the saving of the time or-
dinarily consumed in sighting in ties where grade stakes are
set at intervals of 50 or 100 ft. The surface is sure to be
better where the straight edge is brought into use, and the
danger of kinking rails or bending them out of surface is

1600. Track - Laying Machines. Track - laying
machines have been used to some extent. The ties, as well
as rails and fastenings, are carried on cars. With some
machines they are conveyed to the front on rollers; in
others, on an endless belt which runs along the sides of the
cars. The process of track laying is as follows: Two rail
lengths are laid, bolted, and partially spiked, and the ties
partially bedded. The cars are then run forwards and the
process repeated. The progress of track laying with a ma-
chine is limited by the amount of track which can be full
bolted, spiked, and made fit for the running of trains, and
ranges from 1 to 1 miles per day, 1 mile being a common
average. Economy in the force of track layers and the
saving of team work are the principal advantages claimed
for track-laying machines. In mountainous country, where
the roadbed is difficult of access to teams, the track-laying
machine has decided advantages over ordinary methods, but
in open country where the roadbed is readily accessible,
both ties and rails should be hauled by teams. With



material distributed a considerable distance in advance of
the construction train, a much larger force of men may be
economically employed. If the track laying is to be rushed,
the track-laying machine must take second place.

1 60 1 . Track-Laying Outfit. Before starting out to
lay new track on a new road, the boss track layer should
make requisition for all the tools necessary for expeditious
work. These tools are loaded on a car and shipped to the
point where work is to be commenced. Everything should
be in readiness for making a good beginning before the men
are brought on the ground. Any lack of proper tools is cer-
tain to cause awkward and often serious delay, and opera-
tions must often be suspended until the lack can be supplied
from headquarters. 'The following list of tools will amply
supply a force of 100 track layers, with a reserve for extra
men in case they should be needed, and will be sufficient to
take the places of tools worn out or broken until a supply
can be brought to the front:

Hand cars 1

Steel cars 3

Push cars 2

Shovels 150

Picks 50

Lining bars 12

Claw bars 12

Tamping bars 12

Nipping bars 24

Cold chisels 24

Rail punches 6

Chopping axes 6

Hand axes 6

Striking hammers 42

Bush scythes and snaths,

each 3

Hand saws 6

Adzes 6

Track gauges 12

Covered water barrels ... 2

Track levers 2

Chalk lines 2

Spirit levels 6

Tape lines 6

Nail hammers 3

Monkeywrenches 3

Lanterns, red 3

Lanterns, white 3

Water pails 6

Tin dippers 6

Oil cans 2

Oilers 3

Gallons of oil 2

Pick handles 24

Nails, 10 penny, kegs ... 1
Nails, 20, 40, GO penny,

kegs, of each 1

Cross-cut saws 2



Adz handles 6

Ax handles 6

Maul handles 36

Red flags 12

Sledges, 16 Ib. each 2

Grindstones 1

Track wrenches 24

Iron tongs, pairs 3

Rail forks 6

Expansion shims 200

Switch locks G

Rail drills 2

Torpedoes, dozens 4

Track jacks 4

Rail benders . 2

Curving hooks 2

Post hole diggers 2

Tie poles, 30 ft. long 2

Tie lines, 1,000 ft. long. . 1

Sets double harness 1

Sets single harness 1

Sets double and single-
trees, each 1

Wagon 1

Scraper 1

Horses or mules 2

Tool boxes 2

Files 6

1^-inch rope, feet 300

Car accommodations for track laying should be the

One supply and office car.
One kitchen car.
Two dining cars.
Three sleeping cars.

Where track laying is being done a long distance from
the base of supplies, a blacksmith with forge and tools
should accompany the outfit.

1 6O2. Distributing Ties. When ties are distributed
along the roadbed by teams, they are strung out in proper
numbers, so that the labor of carrying them to their place in
the track may be as light as possible. The largest of them are
reserved for joint ties, the joints being located by measuring
from the ends of the rails already in place in the track. By
measuring with a 30-foot pole, the joints of rails may be
accurately located, a small stake driven marking each joint.
This practice admits of the placing of ties several rail lengths
in advance of the rail, thus affording working room for a
much larger force than could otherwise be handled. A tie
line for lining the ends of the ties is spaced at the proper


distance from the center line and stretched taut, being
fastened at suitable intervals by well-driven stakes. Joints
should not be located at any considerable distance in ad-
vance of the rails, as the measurements are likely to vary a
little and soon accumulate an error. These inaccuracies
are obviated by checking the measurements frequently from
the ends of the rails already in place in the track. Care
must be taken to place the ties at right angles to the center
line. Ties laid askew prevent proper gauging of the track.
Ties should be assorted with reference to thickness in order
that those of uniform thickness may come together in the
track, thus greatly reducing the labor of bedding.

1603. Bedding Ties. As soon as the ties are dis-
tributed and lined they are bedded for the rails. The process
is as follows : The straight edge is placed on the grade stakes
and the faces of the ties brought to a uniform surface by
first sinking those which are above grade and then raising
those remaining to grade by throwing dirt or ballast under
them and settling them to the correct level. It has been a
general and most pernicious custom to spike the rails to the
ties without bedding. Most rails will be found to carry
from one to a half dozen swinging ties, some of which are
sure to get skewed before the ballast secures them. The
track is full of undulations and as the foundation is rough
and uncertain, many of the rails are kinked or surface-bent
by the passing construction train. Where ties are bedded,
the spiking can be better and more expeditiously done, and
the construction train can follow at once with entire safety.

If the track is to be ballasted with cinders or broken stone,
the ties must not be bedded, in order that the ballast may
occupy all the vacant space in the roadway. Nevertheless,
the dressing down of uneven places in the roadway before
distributing the ties is time and money well spent. The
ballasting must be kept well up with the track laying ''if
kinking of the rails is to be avoided.

1604. Organization of Forces. The foreman i:i
charge of track-layers should thoroughly organize his forces^



placing each man where his work will give the best results.
Spikers and iron men are first choice. They should be alert,
sober men, and should be paid higher wages than the rest,
as upon their efficiency depends the excellence and progress
of the work. The prospect of promotion which is thereby
held out lo the others promotes the industry and discipline
of the entire force.

A small surfacing gang immediately follows the track-
layers. Any scarcity of men at the front can be supplied
from this gang, and any extra men at the front can at any
time be profitably added to the surfacing gang.

1605. Locating Joint Ties. The foreman should
detail two trustworthy men to locate the joint ties. They
carry a measuring pole of the standard rail length, usually
30 feet, and locate the joints by measuring from the ends of
the fixed rails. They also complete the work of spacing the
intervening ties, which can not be done until after the joint
ties are placed.


1606. There are two forms of rail joints in general use,
viz., suspended and supported. Both forms have merits
peculiar to themselves, but both are rarely found on the

FIG. 489. FIG. 490.

same road, either one or the other being used exclusively.
A cut of a suspended joint is given in Fig. 489, and of a


supported joint in Fig. 490. In the suspended joint there
are two joint ties spaced about 6 inches in the clear. The
joint is spaced midway between the ties, which should be
carefully selected, have broad faces, and be of uniform thick-
ness throughout. In the supported joint the tie is placed
directly under the joint. The angle splices A and B y which
are shown in section at C, vary in length from 24 to 36 inches.
Those 24 inches in length have 4 bolts, and those from
30 inches upwards have 6 bolts. A joint to be perfect should

Online LibraryInternational Correspondence SchoolsThe elements of railroad engineering (Volume 2) → online text (page 29 of 35)