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A JOURNAL OF HIGHWAY RESEARCH

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DUBLIC ROADS

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UNITED STATES DEPARTMENT OF AGRICULTURE

BUREAU OF PUBLIC ROADS

VEG) Leg IN COS, a= V AP Rik isa

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ROADSIDE TREATMENT ON A MASSACHUSETTS STATE HIGHWAY

U.S. GOVERNMENT PRINTING OFFICE: 1328

PUBLIC ROADS

A JOURNAL OF HIGHWAY RESEARCH U. S. DEPARTMENT OF AGRICULTURE BUREAU OF PUBLIC ROADS

CERTIFICATE: By direction of the Secretary of Agriculture, the matter contained herein is published as administrative information and is required for the proper transaction of the public business

The reports of research published in this magazine are necessarily qualified by the conditions of the tests from which the data are obtained. Whenever it is deemed possible to do so, generalizations are drawn from the results of the tests; and, unless this is done, the conclusions formulated must be considered as specifically pertinent only to the described conditions

VOLES NOe2 APRIL, 1928 R. E. ROYALL, Editor

TABLE OF CONTENTS

Page How Massachusetts is Improving Her Roadsides : ; a 23 Power-Shovel Operation in Highway Grading—Part III ; ey, Motor Vehicle Registrations and Revenues, 1927 ; . 48 THE VU. S. BUREAU OF PUBLIC ROADS Willard Building, Washington, D. C. REGIONAL HEADQUARTERS Mark Sheldon Bldg., San Francisco Calif. DISTRICT OFFICES DISTRICT No. 1, Oregon, Washington, and Montana. DISTRICT No. 8, Louisiana, Alabama, Georgia, Florida, Mississippi, Box 3900, Portland, Oreg. South Carolina, and Tennessee. DISTRICT No. 2, California, Arizona, and Nevada. Box J, Montgomery, Ala. Mark Sheldon Bldg., San prenclsce, Calif. DISTRICT No. 9, Connecticut, Maine, Massachusetts, New Hampshire, DISTRICT No. 3, Colorado, New Mexico, and Wyoming. New Jersey, New York, Rhode Island, and Vermont. Re ee 4 EE ae ates ne F Federal Building, Troy, N. Y. - Fs ta, t ta, t ta, Mepueerrne ; 2 : teas a taint eee STS TRIG EN ce 10, Delaware, Maryland, North Carolina, Ohio, 410 Hamm Building, St. Paul, Minn. Pennsylvania, Virginia, and West Virginia. DISTRICT No. 5, Iowa, Kansas, Missouri, and Nebraska. Willard Building, Washington, D. C.

8th Floor, Saunders-Kennedy Building, Omaha, Nebr.

DISTRICT No. 6, Arkansas, Oklahoma, and Texas. DISTRICT No. 11, Alaska.

1912 F. & M. Bank Building, Fort Worth, Tex. Goldstein Building, Juneau, Alaska. DISTRICT No. 7, Illinois, Indiana, Kentucky, and Michigan. DISTRICT No. 12, Idaho and Utah. South Chicago Post Office Building, Chicago, III. Fred J. Kiesel Building, Ogden, Utah.

Owing to the necessarily limited edition of this publication it will be impossible to distribute it free to any persons or institutions other than State and county officials actually engaged in planning or constructing public highways, instructors in highway engineering, periodicals upon an exchange basis, and Members of both Houses of Congress. At the present time names can be added to the free list only as vacancies occur. Others desiring to obtain “Public Roads” can do so by sending 10 cents for a single number or $1 per year to the Superintendent of Documents, U. S. Government Printing

Office, Washington, D. C.

HOW MASSACHUSETTS IS IMPROVING HER ROADSIDES

Reported by R. E. TRIBOU, Assistant Highway Engineer, District 9, United States Bureau of Public Roads

HE WORK of roadside treatment which Massa- li chusetts started in 1921 has within a relatively few years produced a marked effect on the beauty of its highways, which will be even more striking in future years. Massachusetts is one of the few States where organized attention is given to roadside beautification and because of the general interest in the subject it appears to be worth while to present a short description of the general plan of beautification and methods of handling the work which have produced good results on a considerable mileage of road at a very reasonable cost. -

Pp

a nursery at Palmer, Mass., where trees and shrubs are propagated and where J. H. Taylor, highway landscape supervisor, trains men in the care of trees and roadside beautification. This nursery is a part of the maintenance division. The following outline shows the scope of the work being done.

ATTENTION TO NATIVE MATERIAL

Removal of dead materral—Dead and dangerous branches are systematically removed. ‘Trees entirely dead are removed and stumps cut 6 inches below the eround surface.

A BorRDER PLANTING

The Massachusetts Department of Public Works is empowered by law to make roadside improvements, the work including such plantings, replacements, and care as may be necessary. When a road is laid out as a State highway, it is generally made sufficiently wide to provide an area on each side of the traveled portion for roadside improvement. No tree, shrub, or plant within such a highway can be cut, removed, or new ones added without a permit from the highway department.

The work of roadside improvement is done by the maintenance division of the department of public works which is in charge of G. H. Delano, highway engineer. The cost is included as a part of the regular maintenance expenditure of the State.

96225—28——1

The State has

First aid to “injured trees—Mechanical wounds to trunk or branches are trimmed and _ sealed with tar. Trees split or in danger of splitting are

fastened with bolts or cables. Open cavities are suitably repaired.

Care of trees—Unsightly, abnormal, or rubbing branches are removed. Pruning and shaping is done by trained men. Spraying is done when necessary. Preservation and culture of natural growth is important work. Intelligent care of this sort will add much to the future beauty of roadsides.

Safety work.—Standard traffic clearance is main- tained.

Landscape cutting.—Vistas of mountains, lakes, and streams are developed by removal of foliage screens.

25

PUBLIC ROADS

Vol. 9, No. 2

oe = ——$ $$ ie

READY FOR A PINE PLANTING TRIP

Wire clearance work.—The State supervises all tree trimming for passage of public service wires and pro- hibits careless and unnecessary cutting.

Public enjoyment and education.—Roadside springs are made available to travelers. Benches are pro- vided in suitable places. Public cleanliness is invited by placing rubbish barrels.

INTRODUCTION OF NEW MATERIAL

Healing construction scars—Gravel and sand slopes are planted with small pines or other adaptable ground cover. Grass or shrubs are planted where the soil will support growth.

Tree and shrub planting —Trees, shrubs, and vines adapted to soil conditions are planted on roadsides, traffic islands, behind guard rails or stones, etc.

Replacements.—Historical and normal growth is per- peace by annual replacement of the dead with the

iving.

Maintenance.—The success of all planting depends solely upon maintenance. Young trees and shrubs must have care. The future beauty of trees depends

A Bare Sanp BANK RELIEVED BY PLANTING SwEET FERN

largely upon their training in youth, which means that trees should be staked and pruned annually and intelli- gently. Shrubs must be cut back properly to insure a graceful maturity and soil about the base of all planted stock kept open for proper moisture and air. Such work is imperative and must be done regularly.

The men engaged in this work are advised to study how nature plants and imitate it as far as possible. The object is to keep the roadsides as natural as possible by the use of native material. A Colorado blue spruce on a Massachusetts roadside is distinctly out of place and artificial since it is not characteristic of Massachusetts. Importations may be attractive but they do not reflect the personality of the State.

Plantings on roadsides are mainly confined to new construction for several reasons. ‘The wider locations (60 feet or more) give more opportunity for scenic development, and these relocated and widened roads promise a fairly undisturbed future. Shade trees are planted as near as possible to the side line, but for the most part the monotony of straight lines and even spacing is avoided. Grouping of trees and shrubs is at all times preferable.

Planting procedure.—After a construction job is com- pleted the plan of treatment is determined by an employee trained in the work, who locates the various plantings on a blue print of the layout, using colored pencils. Next the ground is staked for digging. Dig- ging costs are decreased 50 per cent and an extended area is stirred up when holes are blown by dynamite. Pits are filled with the best soil obtainable.

An order for the necessary planting material is for- warded to the nursery and the material is delivered by trucks and trailers. Plantings are carefully made, giv- ing the trees or shrubs every opportunity to get a good start and each planting is staked. After the planting has become well established a final grubbing is given.

The results which are being secured are best described by the accompanying illustrations which were taken by Mr. J. H. Taylor, Highway Landscape Supervisor.

PUBLIC ROADS

April, 1928

&

AP as

om em gle wring.

FBP as eT eee et

OF THE SECONDARY GROWTH

Srumps ReMovep, ALLOWING Rapip DEVELOPMENT

Vol. 9, No. 2

PUBLIC ROADS

BEFORE LANDSCAPE CUTTING

CAPE CUTTING AT THE LOCATION SHOWN ABOVE

ULT oF LANDS

ES

THE R

PUBLIC ROADS

AFTER LANDSCAPE CUTTING AT THE LOCATION SHOWN ABOVE

PUBLIC ROADS

Vol. 9, No.2

: Pe:

DEVELOPING A GROUP OF BIRCHES

Grey Brrcw, WITH BrusH AND Lower Limsps REMOVED FOR TRUNK EMPHASIS

April, 1928 PUBLIC ROADS 3}

A WAYSIDE SPRING DEVELOPED

Tree Surcery Can GREATLY IMPROVE TREES OF UNDESIRABLE SHAPE. AS A RESULT OF 20 MiNuTEs’ WorRK ON THE TREE SHOWN AT THE Lert It Has BEEN CONVERTED INTO A TREE OF Mucu BETTER PROPORTIONS

32

PUBLIC ROADS

Vol. 9,

No. 2

CLOVER ON CHIPPED STONE AND GRAVEL BANK 41 Days AFTER SowiNaG SEED

PINE PLANTING IN UNTREATED BANK

April, 1928 PUBLIC ROADS

2 ~

THE ELDERBERRY 18 WORTH SAVING

en oe a. ee

Poe ¢ ‘Ps ' a SorrTeENING THE HarsH LINES OF PROTECTIVE STONES

96225—28——2

PUBLIC ROADS

A Beacn PLtuM BorDER ON CAPE Cop

Vol. 9, No. 2

April, 1928

PUBLIC ROADS

THE GLORY OF COMMON THINGS

LANDSCAPE GREATLY IMPROVED BY A TREE PLANTING ALONG A BOARD FENCE

36 PUBLIC ROADS Vol. 9, No. 2, April, 1928

A RS Mein Tt

AN EXAMPLE OF Wuat Can BeE DONE By REMOVAL OF TELEPHONE POLES AND WIRES. THE WIRES SHOWN IN THE Upper PICTURE ARE CARRIED IN A CABLE SHOWN AT THE LEFT IN THE LOWER PICTURE

Has BrEN COVERED WITH HONEYSUCKLE

R. W. CRUM APPOINTED DIRECTOR OF HIGHWAY RESEARCH BOARD

Announcement is made by F. H. Eno, chairman of the executive committee of the highway research board of the National Research Council, of the appointment of Roy W. Crum, of Ames, Iowa, as director of the board, effective April 1, 1928.

Mr. Crum’s experience in research work well qualifies him for this position. After graduation from the lowa State College in 1907 he was engaged on the engineer corps of the Pennsylvania Lines, follewing which he returned to Iowa State College as associate professor of civil engineering. He remained in this position for 12 years, during which time he was engaged on research work for the Iowa experiment station. Since 1919 he has been engineer of materials and tests with the lowa State Highway Commission where he has conducted many highway research studies. Mr. Crum has been a member of the committee on character and use of road materials since the organization of the board, and in 1925 he was appointed chairman of the culvert eon conducted by the highway research board. .

Mr. Crum is the author of a number of important research papers. He is a member of the American Society of Civil Engineers, the American Society for Testing Materials, and the American Concrete Institute and is active on several research committees of those organizations.

POWER-SHOVEL OPERATION IN HIGHWAY GRADING

A REPORT OF OBSERVATIONS MADE ON GOING PROJECTS BY THE DIVISION OF MANAGEMENT, BUREAU OF PUBLIC ROADS

Reported by T. WARREN ALLEN, Chief, Division of Management, and ANDREW P. ANDERSON, Associate Highway Engineer

PART 3.—HAULING WITH TRUCKS AND LARGE TRACTOR-DRAWN

RUCKS of various kinds are frequently used to | transport the output of power shovels on high- way work. The bureau’s studies indicate that opinion is far from uniform as to the most desirable type of truck or on such points as tire equipment, carrying capacity, dumping arrangement, and body types. Practically all of the common types of trucks now in use for general hauling have been found on grading projects and in capacities ranging from the light 1-ton to the heavy 7-ton truck.

With such diversity of types, it is only natural that wide variations should also be found in the efhiciency with which they meet the specialized requirements of highway grading. Moving material from the shovel to the dump is quite different from highway transpor- tation and there is little or no dependable data to eulde the grading contractor in selecting trucks for hauling. Both successes and failures have been found during these studies. It appears worth while to discuss in some detail the requirements and conditions under which the truck may be used to good advantage and also the conditions which sometimes make their use inadvisable.

The truck is a well-built, dependable machine, but moving material from the shovel to the dump sometimes offers so many adverse conditions such as soft ground, rough going, and difficult grades that there is probably no field in which operating conditions are more variable and severe. Wear and tear on vehicles is often exces- sive, the speed much reduced and operating costs abnor- mally high when compared with production. This is a condition which should not be attributed to short- comings of the truck as a hauling unit but is due very largely to poor judgment in selecting trucks for jobs to which they are not suited, to selection of the wrong kind of trucks or to lack of ability in their management on the job.

TIME CONSTANT FOR TRUCKS STUDIED

The operation characteristics of the truck differ considerably from those of the team and wagon. The first and perhaps the greatest difference is in the time constant, that is, the time required to take on the load, to dump it, and to perform all turning and maneuver- ing, together with such waits and delays as may be necessary on each round trip. For a two-horse team and wagon the time constant may be as low as one minute and should never exceed two minutes in good common excavation. Tables 1 to 3 show the results of time constant studies on typical jobs using different makes and sizes of trucks, and Table 4 shows the aver- age value of the time constant on each of these jobs.

The loading time is, of course, entirely dependent on the capacity of the hauling vehicle and the rate of shovel output. So long as trucks can be exchanged during the shovel cycle this item need not be given consideration in the selection or control of the hauling equipment. The time required to dump a heavy load is often comparatively large, especially if the material

WAGONS

is very sticky. The lightest trucks used in this work are generally equipped with gravity-dump_ bodies. Practically all others are equipped with a mechanism for raising the front end of the truck body to an angle at which the material is supposed to slide out through the unlatched rear gate. Both the rate at which the hoisting mechanism operates and the angle to which it will tilt the body vary considerably with different makes. During two of the one-hour studies on job No. 44 (Table 1) the average dumping time exceeded two minutes due to adhesive material or large chunks wedging in the body. Tables 1 to 4 show, however, that- the dumping time for trucks in good condition and under average operating conditions may be expected to vary between 15 and 25 seconds for light, l-ton trucks, between 30 and 45 seconds for medium trucks, and from 50 to 80 seconds for heavy trucks.

RoaDWaAyY IN Goop CONDITION AND TRUCK SPOTTED FOR LOADING AT THE SIDE

TIME LOSSES DUE TO TURNING AND BACKING GENERALLY AN IMPORTANT ITEM

Trucks must generally be turned around twice with each load carried except on some short haul work. This takes time because under most ordinary condi- tions some backing is required. The roadway width varies a good deal in different States. A width of about 30 feet is perhaps the most common but it is not unusual to have a width of several feet more or several feet less. Thirty feet of width is sufficient for quick turning if it can all be used, but usually a strip some 5 feet along the edge of the dump is so soft that it will hardly carry the weight of an empty truck. The usable area is often so restricted that the truck has to pull forward and back a number of times before it can complete the turn. In a through cut the con- dition is not apt to be so bad but even here it is seldom possible to make the turn without some backing. The time used in turning, as obtained on several jobs, is shown in Tables 1 to 4. For the heavier vehicles the total time required for turning and spotting to receive and dump the load during each round trip is rarely less than 75 seconds and may under adverse conditions exceed 3 minutes. Where the operating space is

od

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TABLE 1.—Time constant studies on two jobs using 844-ton trucks (make A!) and 34-yard power shovels; each entry is the average of a one-hour study

JOB NO. 41

{Time constant, 272.1 seconds]

| . | De ceenell Dippers | + oading | Waiting | Turning | Dump- eae per load at dump | at dump ing sional ) | | Number . Seconds | Seconds | Seconds | Seconds | Seconds cr 0 i ieeo 2.5 24.5 30,2 23. 0 5.0 | i7.4 a3, 2 a0. 2 56. 4 25.4 483 29 32 17.0 29.7 28.8 20.3 6.0 m7 2.4... 18.5 25.5 he 5s ) fe) 2. 3S a2. 2 29, 2 20. 2 6.0 | 189.0 ; 68.0 22.0 29, 3 24.5 6.0 190.0 | foo 24.0 31.7 24,1 6. 1 | 164.4 x, 4 25.4 25,4 21.6 61 | eo @ ~ oes aee7 29. 0 19.8 6. 0 Pa yaa a 26. 3 aa. 3 23.8 6.0 co ——e 25.7 28.7 24.6 6.0 ou 2... 21.4 35.2 29. 2 Av. 5.7 | 177. 6 14.0 23.9 33. 0 23.6 JOB NO. 44 {Time constant, 290. 8 seconds] | a >: eel , oat) 7 an | ee . ihe 26.3 33.9 3.4 82.4 498 | 15.0 132.0 40. 0 3.0 67.5 3397) | 15.0 63. 0 48, 5 an3 92.3 wes: tO 122. 0 47.6 | 4.2 72.5 6.2 15.0 53.5 15.0 3.8 91.2 79.5 14.7 Bl. 7 62, 2 | 4.0) 0 T.-.. 2! 13.5 20.5 53.5 4.0 79.0 16.2 12.6 22. 6 59, 4 4.0 74,2 38 @ 4 226 25.0 4.0 i a 2 11.4 21.0 42.8 4.0 80. 0 45.6 is. 2 oae2 2x, 0 4.0 101.0 17.47 TG 19.8 27.8 Ay. 3.6, ‘eine 108.7 | 14.0 46.5 40.2

1Tn this discussion letters have been substituted for the names of truck manu- facturers.

TABLE 2.—Time constant studies on two jobs using different sizes and makes of trucks; each entry represents a single observation

344-TON TRUCKS (MAKE B), LOADED BY A 1-YARD POWER SHOVEL

{Time constant, 274.4 seconds}

Dippers Loading Waiting | Turning | Dump- ne per load at dump | at dump ing eouel ——— | Number Seconds | Seconds | Seconds | Seconds | Seconds 5 I i. ee 2 Zz 44 5 ISO) al Seen 30 16 50 D Wa es |. so. 16 M7 36 6 209 co... ee oe On 102 6 BBG) |=-sseaceee Zs 57 40 6 PAS ane |. ee 10 7 26 5 TGA |. ee Pai 24 29 5 | i ee 58 40 36 180 a 30) 48 4 5 Van io UG 24 44 is (Ee Mie Oe 24 Zi 23 5 138 17 15 49 5 140 40 3Y 45 5 2 rn eee oe 26 19 32 iF io Ee 2. 26 a 56 G 135 | . 42 30 58 5 {CGE fies ie" 20 ie 35 6 200 |.......... 16 30 30 6 264 ae 4] 36 39 5 175 es 38 20 62 Awe 5.3 WAQRO. Vee | 29.0 29, 2 43.3 i :

restricted trucks with a short wheel base have a definite advantage, and save much time.

With rear-wheel drive it is often impossible to take full advatange of the minimum radius on which a truck will turn and this is especially true where ground condi- tions are bad and the vehicle will stall if the front wheels are cut the maximum amount. For this reason it is not to be expected that a truck will turn on as short a radius under the conditions commonly prevail- ing on a construction job as it will turn on an improved highway.

PUBLIC ROADS

Volty, INO. 2

TABLE 2.—T ime constant studies on two jobs using different sizes and makes of trucks; each entry represents a single observation—Con.

1-TON TRUCKS (MAKE C), LOADED BY A %-YARD POWER SHOVEL

{Time constant 114.3 seconds]

Sie. ae P Turning Dippers ewan Waiting | Turning | Dump-

g at per load at dump : at dump ing aicuel Number Seconds | Seconds | Seconds | Seconds | Seconds

1 1 ere 24 37 2 GO: sleek 2 40 55 15 1 Po Wes cee 32 ff 56 iI 20 |e 17 83 32 1 6 48 28 13 36 1 18 78 10 12 24 2 7 a ene ier eee 28 at 20 4 31 il 39 26 18 2 aa eee eee 24 26 21 2 46). |Seaeeeecn 36 i 20 . NS |e ee ee 28 24 20 2 Beef ete 2 oo 24 41 2) 2 “RES eee ee 25 12 24 2 42 1 166 23 10 19 Z | i.) eee 17 15 21 2 5 | ee as eae oe 19 19 2 Sas WA sae rts ily 13 22 2 ot, |Geee ae! 19 ps) i 2 Si jae teeta 28 14 13 2 | Sie ic ee oe 45 40 16 | Av.1.75} 33.3 | 6.9| 26.0 24. 5 23. 6

1 Not included in average.

TABLE 3.—T7" me constant study on a job using 5-ton trucks (make D), hauling over an old road surface in good condition, each entry represents the average of a days study

{Time constant, 536 seconds}

Dippers | y oading | Waiting | Turning | Dump- Turning | per load at dump | at dump ing hovel Number | Seconds | Seconds | Seconds | Seconds | Seconds 5.0 140 232 57 122 138 (ees 339 14 a7 110 98 20 261 45 68 88 96 9.3 387 120 89 59 62 7.5 400 298 63 43 64 6.0 Zee 39 61 68 80 6.7 214 10 95 84 92 1a g 250 oe 62 65 58 6.3 250 98 93 64 47 6. 7 234 49 118 57 §1 4.8 173 Wy 88 46 53 5.0 187 47 54 65 60 5.3 185 61 44 135 49 5.7 252 7 60 43 46 6.3 207 46 37 53 55 4.3 160 239 76 41 45 4.7 166 187 57 50 45 Av. 6.6 240 91 68 70 67

TABLE 4.—Average value of time constant with various types of trucks; each entry is average found for a job study

Dip- Wai Total ait- | Turn- Turn- Kind of equipment an, ae ing at | ing at ea ing at a Von: dump | dump shovel Stout ae ae | aaeiaal

Number, Seconds; Seconds) Seconds; Seconds Seconds! Sage 314-ton, make A......... §.7 177. 6 14,0 23.9 33. 0 23. 6 Ziae 314-ton, Make A_.______. 3. 6 81.4 108. 7 14.0 46. 5 40. 2 290. 8 3l4-ton, make B_.__._-_. 5.3 W250 | eee 29. 0 29. 2 43.3 274. 4 5-ton, make D....__- non ors 6. 6 240. 0 91.0 68. 0 70. 0 67. 0 536. 0 l-ton, make C_....._..-- (1a oo 6.9 26.0 | 24.5 | 23. 6 114.3 Backing frequently increases the time constant. The backing speed of most trucks is relatively low. In

spite of this handicap trucks are quite often backed a much greater distance than is necessary in getting into position at the shovel and are often backed into posi- tion at the dump. Some backing may be desirable and it has been pointed out that sufficient attention is seldom given to spotting the trucks at the shovel

April, 192%

TABLE 5.—Hauling speed and time constant on a job where 5-ton trucks (make D) with solid tires were used; each entry is the

{The trucks were backed to the dump down a 11 per cent grade with a good surface.

TABLE 6.—Hauling speed on a job where 314-ton trucks (make A) with solid tires were used; each entry the result of a single

The trucks were backed to the dump down a grade varying from 4 to 10 per cent

TaBLeE 7.—Hauling speed of 314-ton trucks (make B) equipped

of 475 feet.

average of one day’s study

Average time constant 208 seconds}

Time constant

Dippers per load

Number ay, 7

Wait- Loading! ing at | ae Haul | dump | 5 Seconds! Seconds Seconds Feet 106 60 ri 340 i 2 eo 51 360 102 9 93 400 90 55 | 79 420 94 31 as 880 |

Round-trip speed

Ti

me

Average speed

| Haulin reverse |

| Seconds Seconds

Return forward:

ve Haulin Return reverse forward

|

| Feet per Feet per minute | minute 13