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lead being 500 feet ?

SOLUTION. The number of trips per day = ^-g= ^ = 86.4 trips.

As 14 trips are required for each cubic yard of material, the number

86 4
of cubic yards handled per day per man = ~ = 6.17 cubic yards, and

the cost per cubic yard to the contractor for loading and wheeling will



be



YY = 19.45 cents per cubic yard.



It will require one picker for each 5 wheelbarrows. Five wheel-
barrows will handle 6.17x5 = 30.85 cubic yards. Consequently, we
must add to the above cost per cubic yard SI. 20, the wages of the

1 20

picker, divided by 30.85, the number of yards loosened, ^T^K

3.89 cents.

In addition to the above items, there must be added the wages of a
foreman and water carrier, one each for a gang of 30 men, of which 24
handle wheelbarrows. A foreman will cost $2.50 per day and water
carrier $1.00 per day, making $3.50 per day. The additional charge

against each wheelbarrow will, therefore, be ' = 14.59 cents, find

this sum divided by the number of cubic yards carried by each wheel-
barrow will give amount to be added to each cubic yard for superin-
tendence and water carrier, or -^-^ = 2.36 cents per cubic yard.



916 RAILROAD CONSTRUCTION.

Placing the various items of cost in order, we have

Cost of wheeling 19.45 cents per cu. yd.

Cost of picking 3.89 cents per cu. yd.

Cost of foreman and water carrier 2.36 cents per cu. yd.

Wear of tools and wheelbarrows 50 cent per cu. yd.

Total cost to contractor 26.20 cents per cu. yd.

Add 15 per cent, for contractor's profit. . 3.93 cents per cu. yd.
Cost to R. R. Company 30. 13 cents per cu. yd.

A contractor can not undertake wheelbarrow work under
30 cents per cubic yard, which is much in excess of prices
paid for earth excavation for railroad work in 1894-5. If,
however, the contractor is enabled through the use of the
wheelbarrow to do work which would be difficult to accom-
plish without it, its value is at once manifest, and losses which
he may suffer on sections requiring wheelbarrow work he
can readily make good on sections admitting of more modern
methods.

1494. Cart Work. The cost of loading, hauling, and
dumping material by carts may be calculated in the same
way as in calculating cost by wheelbarrows. An ordinary
earth cart weighs about ton and will carry on an average
$ cubic yard of the various soils encountered in railroad con-
struction, measured in place before being loosened. The
material to be excavated is loosened in two ways, viz., by
pick and by plow. When picks are used, the cut is taken out
complete to grade, commencing where the grade line cuts
the surface of the ground and working backwards, the ma-
terial being hauled and dumped to form the adjacent em-
bankment. The carts are backed up to the breast of the
cut (as it is called), and the material loaded with shovels. A
shoveler can shovel cubic yard of sandy soil into a cart in
about 5 minutes; of loam, in 6 minutes, and of heavy clayey
soil, in 7 minutes. By working constantly without any de-
lays, he could shovel in a day of 10 hours, or 600 minutes, of
light sandy soil, 120 loads; of loam, 100 loads, and of heavy
soil, 86 loads. He will, however, lose about T 3 of his time
through delays in waiting for carts and from other causes.
The cost of loading carts is determined as follows: 600, the



RAILROAD CONSTRUCTION. 917

whole number of minutes in a working day, less 180 minutes
lost through delays, leave 420 minutes actually employed in

work; and = 84, the number of cart loads of light sandy

5

420
soil which will be a day's work for one shoveler; = 70,

the number of loads of loam, and = 60, the number of

loads of heavy soil. The cost of shoveling into carts, with

1 on

wages at $1.20 per day, will be, respectively, - ]j =1.43

84

cents per load for sandy soil; -^ = 1.71 cents per load for

1 20

loam, and t = 2 cents per load for heavy soil. As it re-
quires 3 loads to make one yard, the cost for shoveling per
cubic yard will be 1.43 X 3 = 4.29 cents per cubic yard for
sandy soil; 1.71 X 3 = 5.13 cents per cubic yard for loam,
and 2x3 = cents per cubic yard for heavy soil. The cost
of picking will, of course, be the same as that given in Art.
1493 for the wheelbarrow work, viz., 3.89 cents per cubic
yard. A horse will haul a cart at the rate of about 2 miles
per hour, equivalent to 200 feet per minute, or 100 feet going
and coming per minute, i. e., 1 minute for each 100 feet of
.lead. Besides the time consumed in going and coming to
and from the dump, there is a loss of about 4 minutes to
each trip, which time is consumed in loading, turning, and
dumping. The number of trips per day for each cart will,
therefore, be the number of minutes in a working day divi-
ded by 4 plus the number of 100 feet lengths of lead. For
example, suppose the lead is 800 feet, we will then have

number of cart trips per day = - = 50 trips.

4 -|- b

As 1 cubic yard of material in place, i. e., before being
loosened, will make 3 cart loads, the number of cubic yards
transported by each cart per day will be the number of cart

50

loads handled divided by 3. Accordingly, we have =

o



918 RAILROAD CONSTRUCTION.

16.66 cubic yards, a day's work for each cart. With labor
at $1.20 per day, the expense of a horse will be about $1.00,
the use of cart and harness 25 cents, and as 1 driver at $1.00
per day can attend to 4 carts, the total charge against each
cart will be

Horse $1.00

Cart and harness 25

Driver . . .25



Total $1.50

The cost of hauling per cubic yard will, therefore, be the
cost of cart divided by the number of cubic yards hauled,

$1.50

and we have = 9 cents per cubic yard.
16.66

A man is constantly employed on the dump to assist in
dumping the carts and spreading material in layers, which
will cost an average of 1 cent per cubic yard. A gang of 10
carts will require 1 foreman at $2.50 per day and water car-
rier at $1.00 per day. The cost per cubic yard for superin-
tendence and water carrier will, therefore, be $3.50 divided
by the total number of cubic yards hauled by 10 carts. Each
cart hauls 16.66 cubic yards, and 10 carts will haul 16.06

X 10 = 166.6 cubic yards and - = 2.1 cents per cubic

luO.D

yard.

In hauling loam, the amount of the foregoing items of cost
per cubic yard will be:

Loosening 3.89 cents per cubic yard.

Shoveling 5. 13 cents per cubic yard.

Hauling 9.00 cents per cubic yard.

Dumping and spreading. 1.00 cent per cubic yard.

Superintendence 2.10 cents per cubic yard.

Add for sharpening and

use of tools 50 cent per cubic yard.

Total cost to contractor 21.62 cents per cubic yard.

Add 15 per cent, for con-
tractor's profit 3.24

Cost to R. R. Company 24.86 cents per cubic yard.



RAILROAD CONSTRUCTION. 919

The items given are supposed to include repairs of cart
roads (a very important matter) and the trimming and
ditching of cuts. The cart, like the wheelbarrow, is becom-
ing obsolete in modern railroad construction. Its place is
being taken by road machines, wheeled scrapers, dump cars,
and steam excavators. The pick and shovel are still largely
used, especially on the western plains. Hundreds of miles
of road are built on the level prairies by casting, that is, by
shoveling the material directly from borrow pits at the side
of the roadway into the embankment. The soil is generally
soft enough to move without the use of a pick, and often for
miles the expense of hauling is entirely saved. Under such
conditions earth may be handled at from 14 to 16 cents per
cubic yard at fair profit. The embankment on such sections
has an average height of about 2 feet. Not an economic in-
vestment for the bondholders of the road, but it is often
very profitable for those who sell the bonds.

1495. Wheeled Scraper Work. The body of the
wheeled scraper (see Fig. 413) is of sheet steel about 3




feet square and 15 inches deep, containing about $ cubic
yard when level full. The box is open in front, and can be
raised or lowered and revolves on a horizontal axis. All



920 RAILROAD CONSTRUCTION.

movements of the box are made by means of levers. In load-
ing, the box is lowered so that the cutting edge of the open
front cuts into the ground. A strong team, and usually a
second team called a snatcli team, haul the scraper, which fills
itself in the same way as an ordinary hand shovel is filled.
When full, the box is raised about 1 foot from the ground
by means of a lever, and the snatch team is detached. The
loaded scraper is then hauled to the dump, the dumping
being effected by means of a lever, without stopping the
team, which is constantly moving. The wheels have broad
tires, which prevent their cutting into the ground. Where
wheeled scrapers are used, the material is always loosened
with a plow. The cut is not worked from a breast, as with
carts, but is taken out in successive layers from the full area
of the cut.

The scrapers are loaded while the teams are moving, and
as they are continually in motion, their rate of speed will be
somewhat slower than with carts or wagons. Taking the
rate of movement of scrapers at 150 feet per minute, the
distance traveled in going and coming will be but 75 feet
per minute, or 75 feet of lead per minute. Besides the
actual length of lead, each team will travel about 25 feet
additional in turning and dumping. Hence, the number of
trips for each wheeled scraper per day will be the total num-
ber of minutes in a working day, viz., GOO divided by the
number of 75 feet lengths in the lead -j- 25 feet, and suppo-
sing, for example, there is a total lead of 800 feet, the number

of trips per scraper per day will be - = = 54.54 trips

0*0 11

~7~5
per day, and the number of cubic yards for each scraper

will be 5iM = 27.27 cubic yards per day.
A

It will cost an average of 1 cent per cubic yard to loosen
soils and 1 cent per cubic yard to load and dump them. An
additional charge of T ^ cent per 100 feet of lead must be
made for keeping the road in order.



RAILROAD CONSTRUCTION.



921



Spreading, water carrier, and superintendence will cost
2 cents per cubic yard. A man and team will cost $3.50,
with 50 cents added for snatch team, making $4.00 per day,
the charges against each scraper for hauling. We have,

therefore, the cost of hauling ' = 14.67 cents per cubic

yard.

For handling ordinary earthy material with wheeled
scrapers, the amount of the foregoing items of cost will be
as follows:



Loosening with the plow 1.

Loading and dumping 1.

Hauling 14.

Maintaining road at a cost of ^

cent for each 100 ft. of lead . . .
Superintendence, water carrier,

and spreading .... 2.

Total cost to contractor. . .19.
Adding 15$ for contractor's
profit 2.

Cost to R. R. Company 22.



00 cent per cubic yard.
00 cent per cubic yard.
67 cents per cubic yard.

.80 cent per cubic yard.

00 cents per cubic yard.
47 cents per cubic yard.



92 cents per cubic yard.
39 cents per cubic yard.



1496. Drag Scraper Work. The drag scraper

(see Fig. 414) holds from .15 to .25 of a cubic yard of

material. The same labor
of horse and man is required
for the drag scraper as for
the wheeled scraper, except-
ing the snatch team. The
team will move at the
same rate, viz., 75 feet of
lead per minute, but only
15 feet need be added to
the lead for dumping * and
turning. Drag scrapers are

rarely used for a longer haul than 400 feet.




922



RAILROAD CONSTRUCTION.




RAILROAD CONSTRUCTION. 923

The number of trips in a day for a 400-foot lead will, there-

600 (number of minutes in day) 600 600

fore be _

number of 75 feet length in lead -f- 15 415 5.53

7 ?

108.5 trips at \ cu. yd. per trip = 21.7 cubic yards, the

amount of material hauled by each team per day. As the
team and driver cost $3.50 per day, the cost of hauling

per cubic yard will be ' = 16.13 cents, Other charges

will be the same for drag scrapers as for wheeled scrapers,
and we have the items giving total cost to contractor for
delivering material at the dump, as follows:

Loosening with plow 1.00 cent per cubic yard.

Loading and dumping 1.00 cent per cubic yard.

Hauling 10.13 cents per cubic yard.

Maintaining road, ^ cent for

each 100 feet of lead. . . .40 cent per cubic yard.

Superintendence, water car-
rier, and spreading. ... 2.00 cents per cubic yard.

Total cost to contractor,

exclusive of profit 20.53 cents per cubic yard.

Add 15$ for contractor's

profit 3.08 cents per cubic yard.

Total cost to R. R. Com-
pany 23.61 cents per cubic yard.

The above figures are only approximate, and will vary
largely with conditions. Much depends upon the material
handled, the situation, and the weather; but far more upon
the energy, skill, and judgment of the contractor and fore-



1 497. Work with a Steam Excavator and Dump
Cars. In cuttings from 8 feet upwards, a steam excavator
may be employed to great advantage. A first-class exca-
vator, such as is shown in Fig. 415, will excavate and load
into dump cars 600 cubic yards per day.



924 RAILROAD CONSTRUCTION.

The excavator stands on a track a, and as the material
ahead of the machine is cut away, the track is extended and
the excavator is advanced by means of its own machinery.
This is accomplished as follows: The car axles #, b are fitted
with sprocket wheels driven by pitch chains c. These
chains work on sprocket wheels d, fixed to the countershaft e.
The countershaft carries a pinion, not seen in the drawing,
which is driven by the large spur/", which is itself driven by
a pinion attached to the main shaft g. The main shaft also
carries another pinion which drives the spur //, and the
drum attached to its shaft. This drum carries the chains k
which give to the crane / its lateral motion. The boom m
is formed of heavy steel angles, between which the dipper
handle ;/ works. The power for crowding the dipper out-
wards is applied through the steel rack and the pinion
attached to the dipper shaft, and derived from the hoisting
chain q, where it passes over a pocket sheave r. This
pocket sheave drives the intermediate shaft s by friction
clutch and steel pitched chain.

The dipper / holds from 1 to If cubic yards. The teeth
are of heavy pointed steel and attached so as to be renew-
able. The handle is of oak with racking of heavy cast steel.
Steam is generated in the boiler u, and the machinery is
driven by the engine v. The reversing levers are shown
at w. The excavator crew consists of three men, viz., an
engineer, foreman, and craneman. The duty of the latter
is to see that the jexcavator does full work, i. e., that the
dipper is filled at each cut of the machine. Six pitmen are
required to lay track, see to the shifting of the machine,
and help in shifting cars and making up train loads. The
bulk of the work connected with the shifting of cars and
making up of trains is performed by horsepower.

A pit foreman takes charge of all work not immediately
connected with the working of the excavator. The cost of
an excavator is about $6,000. For interest on same and
wear and tear of machine, charge $10.00 per day.

The several items of cost to be charged to the excavator
will be the following:



RAILROAD CONSTRUCTION. 925

Cost of excavator $10.00 per day.

1 tons coal @ $6.00 per ton 9.00 per day.

Water 4.00 per day.

Oil, waste, etc 3.00 per day.

Engineer 4.50 per day.

Fireman 2.00 per day.

Craneman 3.00 per day.

6 pitmen @ $1.50 9.00 per day.

Foreman 3.00 per day.

Horse and driver for shifting cars. . 2.25 per day.

Total $49.75

At 600 cubic yards per day, the cost per cubic yard for

excavating will be ' ' = 8.29 cents.
000

Teams will haul 6 cars holding 1 cubic yards each and
travel at the rate of 3 miles per hour, or an average of about
260 feet per minute, which will be an average of 130 feet go-
ing and coming, i. e., 130 feet of lead per minute. About
3 minutes are consumed in stopping, dumping, and chang-
ing team for return to the excavator. It will require about
1^ minutes per car to load, making 9 minutes per train of
6 cars. The number of trips per team per day will, there-
fore, be equal to 600, the number of minutes in a working
day of 10 hours, divided by 9 minutes, the time of loading +
3 minutes, the time of unloading -f- the number of 130 feet
lengths of lead. Calculating upon a haul of 1,300 feet equal
to ten 130 feet lengths of lead, we have the number of trips

per team per day = = 27.3. Deducting for de-

y -p 6 -j- 10

lays caused by defective track, derailed cars, etc., 3.3 trips,
we have 24 trips per day for each team. As each train car-
ries 9 cubic yards, the total yardage per team per day is
24 X 9 = 216 cubic yards. The team and driver will cost

$3.75 per day. The cost for hauling will, therefore, be '

= 1. 74 cents per cubic yard. Five men are required to main-
tain the tracks and take charge of the dump, 4 men at $1.25



926 RAILROAD CONSTRUCTION.

per day and foreman at $2 per day, making $7.00 per day.
The cost per cubic yard for track and dump charges will,

therefore, be - = 1.17 cents per cubic yard. It will re-
600

quire 24 cars to handle the materials, at a cost of 50 cents
per car per day, making a total daily charge of $12.00, which,
divided by 600, gives an additional charge of 2 cents per
cubic yard for use of cars. The total cost to the contractor
for excavating, loading, hauling, dumping, and spreading
will, therefore, be as follows:

Excavating and loading 8.29 cents per cubic yard.

Hauling 1.74 cents per cubic yard.

Care of track, dumping, and

spreading 1.17 cents per cubic yard.

Use of cars 2.00 cents per cubic yard.

Total cost to contractor 13.20 cents per cubic yard.

Adding 25^ for contractor's

profit 3. 30 cents per cubic yard.

Cost to R. R. Company 16.50 cents per cubic yard.

On account of the great cost of plant and heavy contin-
gent expenses, the contractor should calculate on a profit of
25 per cent, when making estimates on this class of work.

1498. Rock Excavation. A cubic yard of hard rock
in place, i. e., before being blasted, weighs on an average
1.9 long tons, or 4,256 lb., equal to 158 pounds per cubic foot.
A cubic yard of hard or solid rock when broken up by blasting
so that it may be loaded into carts will occupy about 1.8 cubic
yards of space, or 48.6 cubic feet of space. Each cubic foot

of broken rock will, therefore, weigh ' ' = 87. 6 lb. A cart

will carry about \ of a cubic yard of solid rock, i. e., 9.7 cubic
feet of broken rock, which will weigh on an average 850 lb.,
which is only 50 lb. more than an average cartload of earth.
A horse may, therefore, be expected to haul as many loads
of broken rock as of earth. It will cost on an average
40 cents per cubic yard in place to cover the cost of loosen-



RAILROAD CONSTRUCTION. 927

ing, including sharpening tools, drilling, powder, etc. It
will cost an average of 10 cents per cubic yard in place to
load the stone into carts. As the number of cubic yards of
rock handled per day is less than the number of cubic yards
of earth, the cost of superintendence and of water carrier
will be greater, say 3 cents per cubic yard. Repairs of road
will cost ^ cent for each 100 feet of lead. Dumping and
spreading will cost 2 cents per cubic yard. Carts will cost
same as in earth excavation, viz., $1.50 per day. It will
require an average of 5 minutes to load and dump carts.

EXAMPLE. For a lead of 600 feet, what will be the cost to the con-
tractor for delivering solid rock on the dump ?

SOLUTION. The number of cart trips per day will be 600, the
number of minutes in a working day, divided by 5 + the num-
ber of 100 feet lengths of lead. We have, accordingly, number of

fiOO
cart trips per day = ^ = 54.5 trips. At | cubic yard per cart, the

number of cubic yards hauled per cart per day will be ^ = 10.9

o

cubic yards in place. The cost of hauling will, therefore, be $1.50, the
cost per day per cart, divided by 10.9, the number of cubic yards
hauled per cart, which gives 13.76 cents per cubic yard in place, that
is, of solid rock. We have then for handling solid rock with carts,
the following items of cost, viz. :

Loosening 40.00 cents per cubic yard.

Loading 10.00 cents per cubic yard.

Hauling 13.76 cents per cubic yard.

Dumping and spreading 2.00 cents per cubic yard.

Superintendence and water car-
rier 3.00 cents per cubic yard.

Repairs of road 1.20 cents per cubic yard.

Total cost to contractor 69.96 cents per cubic yard.

Add 15 per cent, for contractor's

profit 10.49 cents per cubic yard.

Cost per cubic yard to the R. R.
Company 80.45 cents per cubic yard.

All stone and detached rock found in separate masses, c6n-
taining not less than 3 cubic feet nor more than 1 cubic yard,
and all masses of rock, slate, or coal, or other rock soft
enough to be removed without blasting, are classified as



928 RAILROAD CONSTRUCTION.

loose rock and may be handled at about half the cost of
solid rock.

1 499. Hand Drilling. Hand drilling is performed in
two ways, viz., by churn drilling and by jumping. A

churn drill is made of a round iron bar about 1^- inches in
diameter and from 6 to 8 feet in length, having a piece of
tool steel a little wider than the diameter of the bar welded
to one end of it. This, after being properly hardened and
sharpened, forms the cutting edge. In ordinary work, the
holes are from i to 2 inches in diameter and from 2 to 4 feet
in depth. Holes drilled with the churn drill are usually
vertical. In drilling the bench in tunnel work the drills are
inclined slightly backwards from a vertical line. In drilling,
the churner raises the drill a few inches, turning it slightly
in the hole and allowing it to fall. The drill in a free hole
rebounds so that but little effort is required by the driller
in lifting the drill. An experienced driller will in a working
day of 10 hours drill from 5 to 12 feet of 2-inch hole, de-
pending upon the character of the rock. In granite or hard
limestone from 7 to 8 feet of If-inch hole is a fair day's
work and from 9 to 10 feet in ordinary sandstone. When
the hole is more than 4 feet in depth, two men are put to
the drill.

The jumper is a short drill which is held and turned by
a man in a sitting posture while blows from 8 to 12-lb. ham-
mers are delivered upon the head of the drill by two other
men called strikers. The average depth of a hole per man
is considerably greater with the churn drill than with the
jumper. The advantage of the jumper lies in its admitting
of drilling holes at any angle and in many places where the
churn drill could not be worked on account of limited
space. In drilling with jumpers, drills of various lengths
are used, depending upon the depth of hole. Drill bits re-
quire sharpening at each 6 to 8 inches of hole. Great skill is
required in tempering in order that the drills may do full duty.

On surface work, good drillers are paid from $1.50 to
$1.75 per day. In tunnel work, from $1.75 to $2.00 per day.



RAILROAD CONSTRUCTION. 929

1 5OO. Percussion Drills. Percussion drills are usu-
ally spoken of as rock drills, and are built to be driven by
steam, compressed air, or electricity. They should be de-
signed for hard service, such as sinking shafts and drilling
tunnels in the hardest rock. They should strike a hard
blow, and be so built as to stand the most severe usage, yet
be readily kept in repair with the facilities available in re-
gions remote from machine shops. They must stand up to
the work of pounding a hole in the hardest kind of rock at
the rate of 150,000 to 200,000 blows a day, with all the
shocks and jars which that would mean. The blow should
be an uncushioned blow ; that is, in steam and compressed
air drills, the exhaust, during the forward stroke, should
remain open until the blow is struck, and none of the force
of the blow should be taken up by a cushion of steam or air
in the front end of the cylinder. The bit or drill proper
must hit the rock, which is the only proper cushioning, and
hit it before the pressure enters the front end. Expansive
working of the steam or air in rock drills, as has been at-
tempted, is a mistake. It is permissible and advisable in
engines where the length of the stroke is fixed and where
the weight of the machine is not of very great account, but
in a rock drill the object is to get the hardest possible blow
from the smallest cylinder and the lightesfmachine. The
smaller and lighter the machine, the less space required for
working and the easier handled. The value of a hard blow
in hard rock is well known. The average drill runner is
not careful to keep his bits sharp, and it is a common sight



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