United States. Inland Waterways Commission.

Preliminary report of the Inland Waterways Commission. Message from the President transmitting a preliminary report online

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In this connection I may call attention to the fact that the prop-
erties and especially the permanence of concrete and brick depend
so largely on the character of the materials used, that these materials
should always be thoroughly tested before being used in important
engineering works. But the determination of these properties requires
tests extending over so long a period of time — in some cases several
years — that in the investigations now underway for the concrete and
brick we are selecting from different parts of the country, sands,
gravels, clays, and stone, which are typical of extensive deposits.


And these investigations being conducted in advance of the actual
construction work, will give the information necessary, both for the
preliminary estimates of cost and for construction, without the loss
m time which would otherwise intervene after the work had been
decided upon, in any part of the country.

Inquiries similar to the above are being made from time to time by
the supervising architect and officers in charge of the public build-
ings of the United States, by the Isthmian Canal Commission, by the
Reclamation Service, by the Bureau of Steam Engineering and the
Bureau of Yards and Docks in the Navy Department, by the Corps
of Engineers of the Army, and other Government bureaus, as well as
by persons in charge of State, municipal, or private construction
work or the various industries throughout l:he country.

All such inquiries illustrate the need for additional authentic
information based upon investigation and experience in connection
with the materials available for such construction w^ork, or fuels
available for power development in different parts of the country.
They also illustrate the fact that this additional information needed
in connection with the w^ork of the Government is the same as that
needed in connection with the development of the industries of the
country, looking in every case to the attainment of higher efficiency
and economy in the use of available materials, whether it be for power,
heat and light, or for construction.

It is with a view^ to aiding in the solution of these problems that the
Geological Survey has been authorized by Congress to investigate
fuels and structural materials; and it is hoped that from time to time
as the results of these investigations are made public, that the infor-
mation obtained for use by the different departments of the Govern-
ment will also prove usefid in industrial development throughout the

The expenditures of the Federal Government for construction work
and for fuels now exceed $45,000,000 per annum, while the expendi-
tures of the country for similar purposes will probabl}^ approximate
$2,500,000,000 per annum.

It is believed that these investigations, which are now being con-
ducted under an advisory board on which each of these Government
bureaus is represented, may render practicable a saving to the Gov-
ernment and to the people of the country a percentage on these expen-
ditures which will increase as the investigations are extended and the
results become available.


In spite of the fact that concrete is being used to a larger extent
each year, yet there are abundant evidences of the fact that the engi-
neering profession is still seriously in need of information concerning
the character of concrete and its behavior under tensile and com-
pression strains; its behavior, in both cold and warm climates, in
river and harbor work when exposed between high and low w^ater;
when exposed to the action of organic or mineral acids, alkalis,
oils, etc.; its behavior under different electrical conditions; and its
behavior under different conditions when made up of varying con-
stituent materials; the manner and extent of the reenforcing of con-
crete, and the percentages of the steel and the distribution of the steel


in the concrete mass; the action of electric currents on this steel, and
on the character and streno^th of the concrete; the manner and effect
of reenforcement to enable it to better withstand compressive stresses ;
and finally the methods to be adopted to make concrete impervious
to passage of water, whether or not under pressure.

These are all matters of increasing importance in view of the
extent to which concrete is being used in the building and engineering
work of the country, under the Reclamation Service, under the
Isthmian Canal Commission, under the Corps of Engineers of the
Army (both for river and harbor works and for fortifications) ; under
the Supervising Architect of the Treasury Department; under the
Bureau of Yards and Docks of the Navy, and other Government
bureaus, as well as in the more varied, and in the aggregate, even
more extensive work of the great railway systems and other private
corporations. State and municipal governments.

The extensive series of investigations made under the technologic
branch of the Geological Surve^^ was begun, some of themj two, and
others three years ago. In view of the fact that two years and in
some cases more time must elapse before concrete masses are thor-
oughly seasoned, or before dismtegrating agents can have acted, the
results of many of these earlier investigations are only now becoming
available for use. One recent inquiry from the supervising architect
has required the making of more than 600 reenforced concrete beams,
each 13 feet long; and the testing of different beams at intervals dur-
ing two years, after they had been seasoned under different conditions.

Other investigations are now well underway, and from time to
time as these results are available they will throw additional light
upon a number of problems mentioned above, though with the ap-
propriation at the disposal of these testing laboratories it has not
thus far been possible to keep pace with the demand for information
coming from these many different sources. The Geological Survey
is endeavoring to study with as much detail as possible the distribu-
tion of the different materials of construction in different parts of the
United States, and the technologic branch of the Survey, as rapidly
as conditions will permit, is endeavoring to determine the character
of these different materials for the Government buildings and en-
gineering work which is now under way or contemplated in differ-
ent parts of the country.

The information obtained in connection with the continuance of
these investigations will have a direct bearing upon the develop-
ment of water transportation in the United States, in at least the
following ways :

(1) It will aid in engineering construction work of the river and
harbor improvements ;

(2) It will aid in the building and construction work for indus-
trial and other developments along the lines of water transportation
where these materials are accessible for the cheap water transpor-
tation ;

(3) They will increase the quantity of this transportation, inas-
much as good clays for bricks and tiles, and good sands and gravels
suitable for concrete construction are abundant along nearly all the
inland waterways. The construction work along these waterways
usually calls for the long distance shipment of only the cement,
which represents only about one-tenth of the total weight of the



For the making of concrete at reasonable cost we need to have
available for use, cement, sand, and gravel or broken stone, all of
good quality. The limestones and clays available for the manu-
facture of cement are so widely distributed in the United States
that the supplies of good cement shoidd become continually cheaper
and more abundant. The supplies of sand, gravel, and good broken
stone suitable for the making of concrete are also abundant and
widely distributed throughout the United States, and are especially
abundant in the regions bordering the navigable streams of the
continent. Concrete is therefore destined to become in the future
much more largely than in the past the material used in the con-
struction of dams and other engineering works for river and harbor

The truth and importance of this statement will be realized more
fully when it is remembered that the supplies of stone suitable for
masonry work are generally located in regions too remote from our
navigable streams to permit of their extensive distribution through
water transportation.

Concrete matenals of the Atlantic seaboard. — Stone, both for masonry
work and for concrete, sand, and gravel deposits are abundant along
the New England coasts, but material for the manufacture of cement
is not found in abundance north or east of the Hudson River.

On the Hudson, between Kingston and Albany, there are some
limestone outcrops and ample clays for the manufacture of cement
and brick. Along the Erie Canal for about one-third of its length
between Troy and Bufi'alo, good cement-making limestone is within
easy reach; while deposits of sand and gravel and broken stone are
abundant both along the canal and along the Hudson River.

Portland cement materials of excellent quality are abundant
along the upper Delaware in the vicinity of Easton and at several
points farther north. The old canal site could be extended so as to
draw cement and other materials from the Lehigh districts of Penn-
sylvania, and through the improvement of the canal this cement
would become available for extensive water transportation along
the middle and south Atlantic seaboard.

In the vicinity of Norfolk, Newbern, and Wilmington, Charleston,
Brunswick, and other points on the Atlantic seaboard there are in
places abundant Tertiary marls and adjacent clays which appear to be
available for the manufacture of cement, though no cement plants
exist at the present time on or near the Atlantic coast south of New

On the Chattahooche, Alabama, and Tombigbee rivers, Tertiary
limestones of excellent quality and nearby clay deposits suitable for
cement manufacture exist along probably 20 per cent of the navi-
gable portions of these rivers. And with the completion of the
Warrior River improvements, cement materials can be utilized from
the Birmingham district, where cheap coal is also abundant.

Mississij^in River. — On the Mississippi River below Cape Girardeau
no limestone suitable for cement making has been found accessible on
the river, but from Cape Girardeau as far north as Minneapolis along
probably 50 per cent of the river's course limestone suitable for
cement manufacture is exposed in the river bluffs, and cheap fuel


can be obtained by means of river transportation. Over all this
upper portion of the river, furthermore, clays for the manufacture
of cement, and sand and gravel of excellent quality for concrete con-
struction are abundant. The sand may usually be dredged from the
river's channel. Magnesian limestone and sandstone suitable for
concrete is found along not less than 50 per cent of this portion of
the river's course.

On the Missouri River good cement materials outcrop from near
Kansas City to above Omaha; also from Yankton to points near
Pierre, S. Dak. On the lower portion of the Missouri River similar
limestone occurs in the vicinity of St. Louis, Sands of good quality
are obtained by dredging throughout all the upper portions of the
river. Crushed stone for concrete work will probably be derived
from all the limestone beds.

The Tennessee River throughout its length from north of Knox-
ville to Paducah, has almost continuously available limestone of
good quality for use in cement manufacture, and the same may be
said concerning the availability of clay supplies. Cheap fuels for
cement manufacture can be obtained from Alabama and Tennessee.

Along the Ohio River from Pittsburg to Ironton a few light beds
of limestone occur near the river and are used at several points in
cement manufacture. From this point to Owensboro, Ky., prob-
ably one-third of the river's course is bordered by limestones and
clays suitable for cement. Sands and gravels occur in the river's
bed and may be obtained by dredging; coal is obtained in Indiana,
Kentucky, Ohio, Pennsylvania, and West Virginia suitable for use
in the manufacture of cement.

The Illinois River is bordered at several points in the vicinity of
La Salle and Utica by limestone, clays, and coals of good quality for
cement manufacture; and there are also along its course abundant
supplies of sand, gravel, and stone suitable for concrete construction.

The Red River and its tributaries northeast of Texarkana passes
through extensive deposits of chalk, which, in view of the proximity
of clays and coals, can be used even more extensively than now for
cement manufacture.

Along transportation routes across the Great Lakes, limestones
suitable for cement manufacture are found at but few places. At
various points on the lower peninsula of Michigan, as at Bay City
and Manistee, near Detroit, and also near Sandusky, Ohio, lime-
stone and marl and clays suitable for cement manufacture exist;
and the sand and gravel deposits are available in the same region for
the making of concrete.

Pacific coast. — Along the Columbia River, sands and gravels and
stone for concrete work are abundant, but no materials are found
suitable for the manufacture of cement. In Puget Sound, on the
Orcas, and San Juan Islands, limestone has been found and suitable
clays occur nearby; and in the adjacent regions of Washington and
British Columbia is abundant coal suitable for making cement.

In the vicinity of Los Angeles arc several deposits of limestone
which are eminently suited to manufacture of cement. Satisfactory
clay deposits and cheap oil fuel are available and give promise of
large development there in the future, and sands and gravel or stone
for concrete construction are easily obtained.

At San Francisco the possibilities of cement manufacture are now
partly developed, but do not promise large future developments.


Sands and gravels are available for concrete construction. Broken
stone is also abundant.


As indicated above, the primary purpose of the investigation of
structural materials now underwaj^ is to obtain and to supply
such information concerning these materials as is needed in con-
nection with the various building and construction work of the

Attention was called above to the fact that considerable time is
required — sometimes two or three years — for the seasoning of con-
crete masses before the series of tests can be completed. It is there-
fore a part of tliis general purpose that these investigations shall be
conducted sufficiently in advance of the actual construction work to
permit of our obtaining during tliis time results which may be re-
garded as conclusive before the construction begins.

The plan of operations involves: (1) Obtaining, largely through
the cooperation of the geologic branch of the Survey, information
concerning the general distribution of the sand, gravel and stone
deposits wliich appear to be available for use in connection wath this
work; (2) to select from different parts of the country nearest to the
places where the officers of the Government plan to do construction
or building work, structural materials (sands, gravel, stone), w^hich
are representative of large deposits of material available for this work;
(3) to test this material not only by a chemical and physical examina-
tion of the material itself, but also by mixing these materials with a
typical cement and using these mixtures in the making of blocks of
mortar, concrete, and reenforced concrete imder a variety of condi-
tions; and (4) after seasoning these masses under a variety of con-
ditions, and for dift'erent periods of time, testing them from time to
time in such manner as will determine their different properties and
their suitability for different classes of construction.

In connection with the inaguration of any new line of investiga-
tions, much time is required for the preliminary work of securing
adequate equipment, in training of experts to take part in these
investigations, in determining exact methods wliich are to be em-
ployed, and in arri\'ing at a certain degree of efficiency and certain
general conclusions through tests made with certain types of materials
which are carefully selected for tliis purpose. The materials to be
investigated must then be selected in sufficient quantity (from 1 to 10
tons each), so that they can be tested under a sufficient variety of
conditions to meet all cases that are likely to arise.

These investigations were inaugurated in 1905; and at the present
time not only has a large amount of information been developed con-
cerning the general properties of concrete and reenforced concrete,
but in addition to this sands, gravels, and stone have been collected
from a number of important localities where Government work has
been planned, and concrete and reenforced concrete made of these
materials have been tested under a variety of conditions.


The results of these investigations are now being published as
rapidly as practicable. Among the conclusions arrived at, a few are


worthy of mention in connection with the problems now under con-
sideration, as follows:

1. The sand, gravel and stone suited for the making of concrete are
so much more generally available on or near the navigable waterways
of the country than is stone suited for masonry work, that concrete
is probably destined to play an increasingly^ large part in engineering
construction for the improvement of these waterways;

2. While future limited tests of local material may be needed as
preliminary to important local construction, yet these general investi-
gations now underway should settle all general questions as to the
availability and value of these materials in advance of the construc-
tion, thus avoiding the long delays otherwise necessary for testing
work before actual construction can be commenced;

3. As concerns the sands, the strength and density of the mortars
is greater when the sand is uniformly graded, i. e., when there is a
small percentage of voids ;

4. Wliile probably no definite law has yet been found by means of
which the strength of mortars or concrete using crushed stone screen-
ings may be foretold from mechanical conditions, nevertheless the
same rule seems to apply for crushed stone as for sands, i. e., the
strength and density are greater as the percentage of voids diminishes.

Letter from the chief engineer of the United States Reclamation
Service as to the relative advantages and cost of masonry, con-
crete, and reenforced concrete:

November 26, 1907.
Hon. T. E. Burton,

House of Representatives, Washington, D. C.

Sir: By reference from the Secretary of the Interior I have received your letter
of November 12, inclosing a letter framed by the members of the Inland Waterways
Commission, making certain inquiries.

At my request the Geological Survey, through its technologic branch, is taking
up the answer to your question regarding the relative advantages of steam engines
and internal combustion engines. The other questions, which I will endeavor to
answer as completely as conditions will permit, are as follows:

1. The relative advantages of concrete and stone construction for dams and other
engineering works.

2. The relative advantages of reenforced concrete for such works and also for
bridges over larger streams.

3. The relative cost of stone, ordinary concrete, and reenforced concrete consid-
ered with special reference to sources of materials in: (1) interior United States; (2)
the Rocky Mountain region; (3) the Pacific slope, and (4) the Atlantic slope.

All of the materials mentioned — plain concrete, building stone, and reenforced
concrete — are up-to-date materials of construction in common use at the present
time and are extensively used by the Reclamation Service and by other construc-
tion organizations throughout the country. The theory of design of reenforced con-
crete has been recently developed and the general use of this material has come
into great popularity in late years. Plain concrete, on the other hand, like building
stone construction, is of ancient origin and use.

A comparison of the relative advantages of the three construction materials in
question requires independent consideration for each structure, based on the eco-
nomical availability of material and the kind of forces to be resisted. For example,
a structure of a given type might properly be built of concrete near lines of trans-
portation where cement could be cheaply obtained, and concrete for the same kind
of structure might be inadvisable in remote regions where cement is veiy expensive
and where good building stone might be convenient. Likewise plain concrete or
stone masonry are not adapted to use for beams, ties, and slabs and whatsoever por-
tions of a structure are subjected to bending and pulling stresses.

The Reclamation Service is constructing two dams under very similar physical
conditions on exactly the same plan and for similar purposes. One of these dams is


being constnicted of concrete and the other of granite masonry laid in cement mortar.
This difference is made because the former structure is located near railroad communi-
cation where cement can be obtained at reasonable cost; while the latter is situated
in a locality remote from railroad commiuiication, reached only by verj'^ difficult
wagon roads and abounding in excellent granite rock, the use of which requires less
cement and gives somewhat better results than obtained by the use of concrete.

The effect of the location of the broad divisions of the country on the relative cost
of plain concrete, reenforced concrete, and stone masonry is not so decided as the geo-
logical differences would indicate. The question of local transportation facilities has
more bearing than the geological formations, hence it is impossible to give any data
of value along this line.

In general, the advantages of each one of the materials may be set down as follows:

1. Plain concrete is advisable for use instead of reenforced concrete in cases where
only compressive stresses are to be resisted and where local conditions make the cost
of steel excessive. It is also preferable in many cases where mere weight is important,
such as in gravity dams, retaining walls, etc., and where in giving a structure the
necessary weight the requisite strength is also attained without reenforcement. It is
also preferable on account of cheapness, in some forms of pavement, etc., where little
strength is required. As compared vnXh stone masonrj^ fabricated from some of the
softer building stones, concrete withstands the actions of the weather better and may
be built into all conceivable shapes without the expense of cutting and dressing.

2. Reenforced concrete is preferable on all work in which tensile stresses are devel-
oped, unless prohibited by local conditions making the cost of steel or cement ex-
cessive. The compressive strength of plain concrete is about ten times its tensile
strength, while steel has a very high tensUe as well as compressive strength. In
compression steel will support only about thirty times the load that concrete will,
whereas in tension it will support three hundred times the load that concrete will.
Any given volume of steel costs about sixty times that of the same volume of con-
crete. Therefore, to support compression loads with concrete costs only about five-
tenths of the cost of such support by steel, and to support tension loads with con-
crete costs about five times as much as such support by steel. Clearly then the use
of a combination of concrete and steel, or reenforced concrete, where compression
and tension are present is an economical process. These conditions exist wherever
bending or pulling stresses abound and, therefore, are prevalent in the whole or parts
of many structures including bridges. On this account engineering practice tends
more and more to the building of structures of reenforced concrete as being the

Online LibraryUnited States. Inland Waterways CommissionPreliminary report of the Inland Waterways Commission. Message from the President transmitting a preliminary report → online text (page 56 of 83)