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TRANSACTIONS



AMERICAN 80CIETY



CIYIL ENGINEERS



(INSTITUTED 1852)



VOL. LXXXI



Edited by the Secretary, under the direction of the Committee on Publications.

Reprints from this publication, which is copyrighted, may be made on condition that

the full title of Paper, name of Author, and page reference are given.



NEW YOKK

PUBLISHED BY THE SOCIETY
I9I7



^ k 5 .Q



Entered according to Act of Congress, in the year 1917, by the American Society of
Civil Engineers, in the Office of the Librarian of Congress at Washington.



Note. — This Society is not responsible for any statement made or opinion expressed

in its publications.



CONTENTS



PAPERS

No. PAGE

1379 DESIGNING AN EARTH DAM HAVING A GRAVEL FOUNDATION,
WITH THE RESULTS OBTAINED IN TESTS ON A MODEL.

By James B. Hays 1

Discussion :

By W. G. Bligh 25

J. C. Oakes 28

C. E. Grunsky 33

H. T. Pease 37

Malcolm Elliott 39

Edward Wegmann 42

E. C. La Rue 43

George M. Bacon 47

H. A. Pettehson 47

D. C. Henny 55

Joseph Jacobs 59

James B. Hays 69

L380 UNDERPINNING TRINITY VESTRY BUILDING FOR SUBWAY CON-
STRUCTION.

By H. de B. Parsons 74

^*"* Discussion :

K.^ By James C. Meem 102

Elias Cahn 103

T. Kennard Thomson 104

James F. Fouhy 107

Charles Rufus Harte 107

Joseph A. A. Connelly 108

J. S. Branne 109

A. W. BUEL 109

H. DE B. Parsons 110

U 1381 SURGES IN AN OPEN CANAL.

> By R. D.' Johnson 112

^ Discussion :

^5 By Karl R. Kennison 116

Y"^ Irving P. Church 119

'J
1382 THE PROPERTIES OF BALSA WOOD (Ochroma Lagopiis).

By R. C. Carpenter 125

Discussion :

/- IT^ By A. P. LuNDiN 156

V_/ Leonard M. Cox 160




IV

No. PAGE

1383 SUGGESTED CHANGES AND EXTENSION OF THE UNITED STATES
WEATHER BUREAU SERVICE IN CALIFORNIA.

By George S. Binckley and Charles H. Lee 161

Discussion :

By N. C. Ghover 171

William S. Post 172

Charles T. Leeds 173

Fred. H. Tibbetts 177

J. B. LrPPINCOTT 181

George S. Binckley and Charles H. 'Lee 184



1384 EARTH PRESSURES: A PRACTICAL COMPARISON OF THEORIES AND
EXPERIMENTS.

By L. D. Cornish 191

Discussion :

By William Cain 202

G. M. Braune 216

F. N. Menefee 218

L. D. Cornish 220



1385 A COMPLETE METHOD FOR THE CLASSIFICATION OF IRRIGABLE
LANDS.

By F. H. Peters 222

Discussion :

By T. Kennard Thomson 243

G. N. Houston 244



1386 THE VALE BOWL.

By Charles A. Ferry 249

Discussion :

By Thomas C. Atwood 280

J. B. French 283

H. C. Keith 285

H. F. Dunham 286

Henry C. Hitt 286

Alexander S. Lynch 290

Charles A. Ferry 291



1387 CONTROL OF THE COLORADO RIVER AS RELATED TO THE PRO-
TECTION OF IMPERIAL VALLEY.

By J. C. Allison 297

Discussion :

By A. L. Sonderegger 326

J. A. Ockerson 333

J. C. ALLISON 333



e^aei



No. PAGE

1388 TUNNEL WORK ON SECTIONS 8, 9, 10, AND 11, BROADWAY=LEX-
INGTON AVENUE SUBWAY, NEW YORK CITY.

By Israel V. Werbin 341

Discussion :

By Maurice Griest 392

John H. Madden 393

Robert H. Jacobs 397

T. Kennaed Thomson 398

John H. Myers 399

h. g. moulton 400

Robert Ridgway 404

C. V. V. Powers 405

Francis Donaldson 405

Israel V. Werbin 408



1389 A METHOD OF DETERMINING A REASONABLE SERVICE RATE FOR
MUNICIPALLY OWNED PUBLIC UTILITIES.

By J. B. Lippincott 413

Discussion :

By Frank S. M. Harris 423

T. Kennard Thomson 424

W. B. Ybreance 426

Leonard C. Jordan 428

H. F. Clark 432

Allen Hazen 435

W. G. Irving 437

H. A. Whitney 438

J. B. Lippincott 444



1390 CONSTRUCTION METHODS FOR ROGERS PASS TUNNEL.

By A. C. Dennis 448

Discussion :

By E. Lauchli 471

Robert A. Shailer 473

R. H- Keays 474

F. Lavis , ,^. ba,:.; 476

James F. Sanborn . ■.-. 478

Lazarus White 478

T. Kennard Thomson 479

Francis Lee Stuart ' 481

J. V. Davibs 483

S. A. Knowles 485

R. E. Dougherty 486

C. R. HULSART 487

J. G. Sullivan 489

A. C. Dennis 494



\^



VI

XO. PAGE

1391 UNUSUAL COFFER-DAM FOR 1 000-FOOT PIER, NEW YORK CITY.

By Charles W. Staniford 498

Discussion :

By Fbedbkic R. Harris 543

D. A. Watt 544

C. A. Wentworth 545

Thomas H. Wiggin 548

T. Kennard Thomson 551

Charles S. Boardman 553

WiLUAM M. Black 569

F. E. CUDWORTH 569

1392 THE VALUATION OF LAND.

By L. P. Jerrard 582

Discussion :

By W. I. King 618

Hugh A. Kelly 619

Edwaed S. Rankin 626

T. Kennard Thomson 628

J. S. Waxker 629

William J. Boucher 631

FRANKLIN P. Mayo 638

L.. P. Jerraed : 639

1393 TESTS OF CONCRETE SPECIMENS IN SEA WATER, AT BOSTON

NAVY YARD.

By R. E. Bakenhus 645

Discussion :

By T. Kennard Thomson 676

J. J. Yates 677

J. R. McClintock 682

S. B. Williamson 683

Waldo C. Briggs 683

Charles S. Bilyeu 684

W. E. Day 684

Robert Ridgway 684

George W. Fuller 685

A. H. Rhett 688

Marshall W. Brown 692

Albert Lahsbn 693

W. Watters Pagon 699

R. J. Wig and Lewis R. Ferguson 703

R. E. Bakenhus 705



1394 AN AERIAL TRAMWAY FOR THE SALINE VALLEY SALT COMPANY,
INYO COUNTY, CALIFORNIA.

By F. C. Carstarphen 709

Discussion :

By Richard Lamb 743

H. F. SCHOLTZ 745

F. C. Carstarphen 745

^ - .-



VII

No. PAGE

1395 THE WATER SUPPLY OF PARKERSBURG, W. VA.

By William M. Hall 749

Discussion : *

By John W. Hill 7S8

Alexander Potter 792

George W. Fuller 796

Nicholas S. Hill, Jr 801

Walter E. Spear 804

T. Kennard Thomson 805

H. F. Dunham 806

Theodore S. Johnson 807

Philip Burgess 811

James H. Fubrtes 821

Morris Knowles and J. D. Stevenson •. . . . 832

Edward Mayo Tolman 838

Wllliam M. Hall 843

1396 MULTIPLE-ARCH DAMS ON RUSH CREEK, CALIFORNIA.

By L. R. Jorgensen 850

Discussion :

By F. O. Blackwell 882

A. D. FriNN 884

F. W. Scheidenhelm 885

Edwabd Wegmann ' 890

Walter J. Douglas 892

Edwin Duryea 894

L. H. Nishkian 898

Gardner S. Williams 899

George W. Howson 900

L. R. Jorgensen 901

1397 THE RECONSTRUCTION OF THE STONY RIVER DAM.

By F. W. Scheidenhelm 907

Discussion :

By J. W. Ledoux 1024

J. K. Finch 1027

P. P. Rutenberg 1029

Fred F. Moore 1035

W. S. Downs 1036

H. L. COBURN 1038

H. F. Dunham 1039

Oerin L. Brodie 1041

William Cain 1044

Charles E. Gregory' 1058

Kenneth C. Grant 1066

L. R. Jorgensen 1070

Edward Wegmann 1071

lR\aNG P. Church 1076

M. M. O'Shaughnessy 1081

Joel D. Justin 1082

Ross M. Riegel 1086

F. W. Scheidenhelm 1087



PAGE

HowAKD Arnold Greene, Assoc. M. Am. Soc. C. E 1800

William Herbert Hyde, Assoc. M. Am. Soc. C. E 1802

.Josfi Petronio Katigbak, Assoc. M. Am. Soc. C. E 1803

George Gere MacCracken, Assoc. M. Am. Soc. C. E 1806

Stanley Hastings McMullen, Assoc. M. Am. Soc. C. E 1808

Philip Henry Paethesius, Assoc. M. Am. Soc. C. E 1810

L.EWIS Roberts Pomeroy, Assoc. M. Am. Soc. C. E 1811

William Thomas Shaw, Assoc. M. Am. Soc. C. E 1813

William Stuart Smith, Assoc. M. Am. Soc. C. E 1815

Samuel Forsythe Thomson, Assoc. M. Am. Soc. C. E 1817

George Edward Vansittart, Assoc. M. Am. Soc. C. E 1821

James Madison Warntsr, Assoc. M. Am. Soc. C. E 1823

William Cooper Cuntz, Assoc. Am. Soc. C. E 1825

George Henky Frost, Assoc. Am. Soc. C. B 1827

James Jerome Hill, F. Am. Soc. C. E 1829



PLAT ES



plate paper paqk
I. Curves for Proportioning Puddle Section of Dam, and Sec-
tion of Original Dam 1379 9

II. Diagram Comparing Experimental with Theoretical Calcu-
lations for Earth Pressures 1384 195

III. Typical Plan of Section of Land, with Topography ; and

Office Classification of Irrigable and Non-Irrigable Areas. 1385 231

IV. Typical Sections in Tunnel, Lexington Avenue Subway, 53d

to 103d Streets, New York City 1389 343

V. Method of Tunnel Excavation, Two-Track Tunnel, in Sound
Rock, Sections 8 and 9, Broadway-Lexington Avenue

Subway 1389 345

VI. Method of Excavation in Unsound Rock, Two-Track Tunnel,

Sections 8 and 9 1389 347

VII. Method of Excavation, Four-Track Tunnel, 100th to 102d

Streets, New York City 1389 371

VIII. Plan and Profile of 45th Street Coffer-dam. New York City. 1391 505

IX. Profile of Stony River Dam, Showing Probable Geological

Conditions 1397 917

X. Typical Section of New Spillway, Stony River Dam 1397 931

XI. Plan of Stony River Dam as Reconstructed 1397 945

XII. Typical Sections of Strengthened Structure, Stony River Dam. 1397 955

XIII. Anchoring Wall at Heel of Outlet Gate Bays, Stony River

Dam 1397 1017

XIV. Diagram Showing Yearly Compensation of Engineers 1399 1209

XV. Diagram Showing Average Yearly Compensation of Engi-
neers 1399 1211

XVI. General Arrangement of Leaf of 77%-Foot Gate, Panama

Canal 1402 1639

XVII. Application of Formulas to Gates of Panama Canal 1402 1641



AMERICAN SOCIETY OF CIVIL ENGINEERS

INSTITUTED 1852



TRANSACTIONS



This Society is not responsible for any statement made or opinion expressed
in its publications.



Paper No. 1379

DESIGNING AN EARTH DAM

HAVING A GRAVEL FOUNDATION,

WITH THE RESULTS OBTAINED IN

TESTS ON A MODEL*

By James B. Hays, Jun. Am. Soc. C. E.



With Discussion by Messrs. W. G. Bligh, J. C. Oakes, C. E. Grun-
SKY, H. T. Pease, Malcolm Elliott, Edward Wegmann, E. C.
La Eue, George M. Bacon, H. A. Petterson, D. C. Henny, Joseph
Jacobs, and James B. Hays.



Synopsis.

The following paper, though giving the theory regarding the design
of an earthen dam having a gravel foundation, is intended mainly
to present the results of tests on a model constructed to scale. The
dam was designed to impound water for storage purposes under rather
unusual conditions. A study of the subject produced little of real
value in determining the action of water under these conditions.

However, this paper does not give the detailed design of unim-
portant features but only the general design, especially the shape and
type of cross-section and the quality of the materials placed therein.

It is hoped that the discussion will bring out many interesting
facts and experiences which will contribute to more rational methods
of design of earth dams, or of any dams, on porous foundations.



Introduction.
At the dam site in question, a dam had been started, but was
wholly unfit to sustain even a small proportion of the head of water
* Presented at the meeting of April 19th, 1916.



2 DESIGNING AN EAETH DAM

required. The reservoir was for the storage of water for irrigation
purposes, and the dam was to be 110 ft. high at the maximum section.
With an approximate depth of 30 ft. of material in place, aud nearly
the whole width of the base, a head of slightly less than 25 ft. caused
water to issue in considerable quantities from the down-stream toe of
the dam. This caused the people living in a small town a few miles
down the river to become fearful of the results.

Several reports, made by different engineers, unanimously con-
demned the structure as it was being built. The bonding house backing
the irrigation company failed at this time, the project was sold to satisfy
judgments, and the contractors for the dam took over the proposition.

At their request, F. C. Horn, M. Am. Soc. C. E., was asked to
submit a design for a dam to be built at the same site, if it could
be done, in order to utilize as much of the existing structure as pos-
sible. On account of the imusual conditions — which will be stated
later — it was decided to make a thorough research, to be followed by
experiments and tests, in order to make certain of the design. The
writer did much of the research work, constructed the model, and
made the tests for, and with, Mr. Horn, which the latter has kindly

made available.

General Conditions.

The stream on which the dam was being built runs southeastward,
and, on the southwest side of the valley there are high cliffs of cherty
limestone near which the stream has its course. On the opposite side
of the valley there are high mountains at some distance from the river.
Mountain streams, rushing along at high velocity, had carried gravel,
sand, and some boulders out into the valley bottom, where the material
was dropped, forming great cones, or fans, of very porous material.
The dam site had been originally selected having one of these gravel
cones as the foundation and northeast bank, this being done with
only a superficial knowledge of the subsurface conditions.

When trouble was reported, work was ordered stopped by the State
Engineer; then a few borings were made and test pits dug, the
results of which were available for the re-design of the structure.
The borings, which were made close to the center line, or axis, of
the dam, show that it would be practically impossible, and useless,
to reach bed-rock throughout the entire length of the dam and thereby
cut off the underground flow of water.



DESIGNING AN EARTH DAM



In the subsoil investiga-
tions, a material was encoun-
tered which was called hard-
pan. Chemical investigation
shows that there is practically
no clay in this material, and,
in fact, no clay in the vicinity.
The material called hardpan
was very fine, gritty, and angu-
lar. It was tightly packed, and
formed a very dense mass.

A large quantity of this
fine material was found on the
surface, about a mile from the
dam, and when shaken down
in a glass container, packed
into a very tight, dense mix-
ture. This material is often
called hardpan, but is not real
hardpan, as it contains no clay.

A cut-off wall of concrete
was built across the river
channel, beneath which steel
sheet-piling was driven into
this so-called hardpan. Some
of the piling was driven 18 ft. £• 3 i.
deep, and other portions sank
as deep as 32 ft. with one or
two blows from a 1 700-lb.
hammer.

^.., The body of the dam was
being built of the same mate-
rial as that composing the
gravel cone at its northeast
end, and, as was shown in
one of the reports, nearly all
the water, except flood waters,
of the creek that had con-




4 DESIGNING AN EAETH DAM

structed this cone was sinking into the gravel and reappearing at a
lower point. This, it would seem, should have been an object
lesson to the original locators of the site, and would indicate
the conditions as to its character. However, little attention seems
to have been given to the matter, and a dam was being built
to hold up a head of 105 ft., to have a top width of 20 ft., with
slopes of 2J : 1 up stream, and 2 : 1 down stream. The down-stream
toe had a gravel or loose rock drain, and the up-stream face had a
concrete facing, which, for some unknown reason, did not extend to
the toe of the dam.

Fig. 1 shows the results of the borings on the center line of the dam.
Thus, it will be seen that the impervious stratum is a very uncertain
quantity, and that bed-i'ock is very deep and practically impossible
to reach with a cut-off wall.

General.

In looking for precedent in the design of a dam under these con-
ditions, Mr. Horn and the writer were confronted with a lack of good
material based on a systematic study of structures of this type, although
several good points were obtained from some of the papers on the
subject.

As these tests, experiments, and designs were made during the
period from August, 1914, to August, 1915, the valuable information
contained in the paper by J. B. T. Colman, Assoc. M. Am. Soc. C. E.,
on "The Action of Water Under Dams",* was not available. Although
Mr. Colman was unable to effect a complete loss of head with his
model, the writer was successful in this, and has explained the differ-
ence in construction of the two models in his discussionf of that
paper, which accounts for the different results obtained. However,
although the writer's experiments cover the design of the dam, as
well as the study of the flow of the underground water, he believes
tliere is much material of a different nature contained in this paper.:}:

The paper§ entitled "The Bohio Dam", by the late George S.
Morison, Past-President, Am. Soc. O. E., contains some interesting



* Transactions, Am. Soc. C. E., Vol. L.XXX, p. 421.
t Ibid., p. 458.

t In Professional Memoirs, U. S. Engineer Corps, Vol. VII, p. 44, par. 33, there Is
a record of an experiment similar to a part of Mr. Colman's.
§ Transactions, Am. Soc. C. E., Vol. XLVIII, p. 235.



DESIGNING AN EARTH DAM 5

points, and the discussion on that paper brings out some good details
regarding the design of the North Dike of the Wachusett Reservoir.
In this structure a deep trench was excavated parallel to the axis
of the dam, and in the bottom of this trench wooden sheet-piling
(some pieces as long as 60 ft.) was driven. Percolation and seepage
experiments were conducted with a tank similar to the one used and
described by Allen Hazen, M. Am. Soc. C. E., in his percolation experi-
ments. In the case in hand, a tank of the same style was adopted for
the preliminary experiments, and furnished much valuable informa-
tion to be used in the final tests. A large wooden tank was also con-
structed for the purpose of studying the probable percolation and
seepage through the structure. In this case (the North Dike of the
Wachusett Dam), the foundation, or subsoil, was not considered in
the tests; thus the conditions differed from those which had to be con-
sidered in the design of the dam described in this paper.

In the North Dike there was a long, rather flat, down-stream slope,
and a steeper up-stream slope. A flat hydraulic gradient, caused
by the water in the reservoir seeping under the dam, called for a
large quantity of material, in order to withstand the upward pressure
under the down-stream portion of the dam. The dam was of such a
length that the water, rising from the down-stream toe, was under
no upward pressure and flowed away without disturbing the soil.

The Gatun Dam, built in connection with the Panama Canal,
was designed and constructed under similar conditions, having a silty
river deposit for a foundation. A flat down-stream slope causes the
percolating water to travel a long distance before a free opening is
encountered, thus causing the upward pressure to be consumed by
friction.

In discussing the paper entitled "Dams on Sand Foundations : Some

Principles Involved in Their Design, and the Law Governing the

Depth of Penetration Required for Sheet-Piling",* G. E. P. Smith,

M. Am. Soc. C. E., works out a very interesting theory,! showing that

the creep, or total distance which the water would travel, would be

increased by an amount equal to twice the length of the sheet-piling

introduced. It is not stated in so many words, but the loss of velocity

in traveling down one side of the sheet-piling and up the other side

• Transactions, Am. Soc. C. E., Vol. LXIII, p. 175.
t Ibid. p. 197.



,t) DESIGNING AN EARTH DAM

amounts to the same as adding twice the length of the sheet-piling
to the length of the base.

W. G. Bligh, M. Am. Soc. C. E., gives a very interesting treatment
of the design of weirs on sand foundations.* His theory is that
the water will follow the line of creep, along the base of the dam,
down one side of the cut-oii wall, up the other side, and con-
tinue along under the base to a free outlet, that is, that pressure
is lost in direct proportion to the enforced line of creep. This
theory gives structures of ample dimensions, as has been shown by
practice, but was found to be incorrect, after due experimenting, as
will be noted later.

E. A. Moritz, Assoc. M. Am. Soc. C. E., has givenf the cus-
tomary method followed by the United States Reclamation Service
Engineers. This, it will be noted, follows the line of creep theory as
described by Mr. Bligh.

D. C. Henny, M. Am. Soc. 0. E., made tests:{: on different com-
binations of the available local materials in order to determine the
tightest mass. Tests for seepage were made with many different
mixtures.

In the writer's method, only one combination of materials was
made, and that was done by a study of the sieve analysis curves. §
Such curves are plotted for the various materials at hand, and
compared with the ideal curve for the densest mass. Experience has
proved that this method gives a very tight concrete. The experiments
described in Mr. Henny's paper did not cover the seepage under the
dam, but adequate drainage was provided in order to forestall the
danger of the down-stream bank sloughing off.

Experiments and Tests.

The foregoing sources of information are mentioned in order to
show what materials were available, to give credit where similar plans
were followed, and, for the sake of comparison, to state where results
differed, which was largely the case.

• "Practical Design of Irrigation Works", Chapter VI.

t "Working Data for Irrigation Engineers", pp. 39-40.

t "Two Earth Dams of the United States Reclamation Service", Transactions, Am.
Soc. C. B., Vol. LXXIV, p. 38.

§ This method is explained in Taylor and Thompson's "Concrete, Plain and Rein-
forced", pp. 194, et seq.



DESIGNING AN EAETH DAM 7

The first experiments were for the purpose of determining the loss
of head due to the water percolating through the various materials.

In the first test the attempt was made to determine the hydraulic
gradient, or loss of head, through the coarse material constituting the
foundation of the dam, and of which a part of the structure was already
built. The tank had a diameter of 30 in., and a total height of 5 ft.
The inside of the tank was given two coats of paint, and was then
sanded in order to prevent possible seepage along its walls. Two glass
tubes extending upward on the outside of the tank were connected
with the inside and arranged to indicate the loss of head between two
points which were vertically distant 3 ft. Fig. 2 shows the tank. A
valve at the bottom held back the water until the pore spaces were
completely filled; then the valve was opened, and after a few minutes
the relative elevation of the water in the two tubes became constant.
The difference in elevation determined the loss of head, and from this
the hydraulic gradient was computed.

The initial run gave a very small loss of head; a few days later,
the loss was greater and remained constant. This is explained by the
fact that the material was placed in the tank in a dry state and the
first application of water readjusted the finer materials into what in
all probability represents the natural condition. With 6 in. of water
on the soil surface, and 8 in. of soil above the upper tube, the loss of
head was 1 ft. in 9.

This gravel was screened into its various sizes, and showed a very
small percentage of fine material. In the upper diagram on Plate I,
Curve A shows this material as plotted. Fig. 3 is reproduced from a
photograph of a sample of this material, and Fig. 4 shows the material
as it stood in the steam-shovel pits from which the dam was being
constructed and from which point the sample was taken.

Having deterrhined the hydraulic gradient of the underground
material, a trial design was made to find what dimensions would be
necessary in a dam constructed wholly of this gravel. The lower
diagram on Plate I shows the dimensions, assuming that the hy-
draulic gradient began at the water surface on the up-stream face of
the dam. The effect of the core-wall on the "line of creep" theory
would be small. The section shown was deemed to be very inefficient
and excessively expensive, on account of the large quantity of material



8



DESIGNING AN EAKTH DAM



to be placed. Further investigations were then made to determine how
the section could be reduced.

Following out the "line of creep" theory as the one which seemed
to be more nearly correct, on account of its practical success, it was
decided that, if a tight material could be obtained for the up-stream
section, the hydraulic gradient could be forced to begin farther up
stream, and thus there would be secured the advantage of the up-
stream section in reducing the upward pressure before the water
reached the portion of the dam below the center line or core-wall.

As mentioned previously, a large body of very fine material was
available in the vicinity. A sample of this material when analyzed gave
Curve B in the upper diagram on Plate I. Curve A showed a lack
of material, which was just balanced by the excess of fine material in
Curve B. By observation, it was determined that, for all practical
purposes, the combination of these two materials in the ratio of 1:1,
would give a very dense mixture which would approach closely the
ideal curve. Curve C represents the combined material. Fig. 5 shows
a sample of the fine material, and Fig. 6 shows the combined material.

TABLE 1. — Mechanical and Chemical Analyses of the Fine Material
Obtained One Mile from the Site of the Proposed Dam.



Mechanical Analysis.
This analysis covers only the material



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