Year: 1896

page_text: Date of Application, 26th Nov., 1896-Accepted, 20th Mar., 1897
I, GEORGE ADAM GEISEL, Manufacturer, residing at No. 204 Wainwright Building,
in the City of St. Louis, State of Missouri, one of the United States of America, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to improvements in concrete bridges; and it consists in the
novel construction, combination and arrangement of parts, hereinafter described and
claimed.
Figure 1 is a longitudinal sectional view of a bridge constructed in accordance
with my invention.
Fig. 2 is a horizontal sectional view on the line 2-2 of Fig. 1.
Fig. 3 is a vertical transverse sectional view on the line 3-3 of Fig. 1.
Fig. 4 is an enlarged longitudinal sectional detail of a modified form of the arch
shown in Fig. 1 and illustrates an arch constructed in accordance with my invention
where long spans are required.
Fig. 5 is an enlarged longitudinal sectional detail of a modified form of the arch
shown in Fig. 1 and illustrates an arch constructed in accordance with my invention
where a very long span is required.
Referring by numerals to the accompanying drawings, the water 1 of the river
rests on the bed 2 between the banks 3 and 4. In each of the banks 3 and 4 an
excavation is made for the abutments 5 and 6 and the wing walls 7, and 8, of the
bridge. Piles 11 and 12 are sunk in these excavations until a solid foundation is
reached. The upper ends of these piles are saved off on a horizontal line about one
foot above the bottom of the excavation. The ground plan of the abutments and wing
walls is shown in Fig. 2, the piling being shown in dotted lines.
After the piles have been driven and sawed off the excavations are cleaned out to
the virgin earth. A layer of concrete about one foot in thickness is then placed in
the excavation and thoroughly rammed around the heads of the piles. Similar layers
of concrete are placed one on top of the other in the excavations until the abutments
and wing walls are of the desired height. Each layer is thoroughly sprinkled with
water before another is added in order to form a thorough bond between the layers.
When completed the whole mass of each abutment and its wing walls is a solid body
of concrete. When the abutinents and wing walls get above the surface of the
ground, suitable false work is erected to mold said abutments and wing walls into the
desired shape. After the concrete work is finished, the false work is left in position
about three days until the concrete has become sufficiently hardened to stand."
On the facing walls of the abutments 5 and 6 are surfaces 13 and 14, forming the
skew backs, upon which the ends of the arch 15 are seated, the lines of said surfaces
corresponding to the radial lines of the arch. The arch is in three pieces, when the
bridge is complete, and consists of the two sides 15 and 15° and the keystone 15°.
The surfaces 13 and 14 are covered with tar paper or other suitable substance, to
prevent the arch from forming a bond with the abutment. The side pieces 15 and 15°
are each constructed in five sections 15, 15, 15', 158, 15, 15', 15, 15, 15' and 15.
In constructing the arch I work from each end towards the center. The end section
is cast and before it has time to set, the next section is cast and a bond forms between
them, and so on until the pieces 15" and 15" are complete. At the boundary line

page_text: between the second and third sections from the outer ends of the pieces 15 and 15
the arch is between thirty-five and forty per cent. thicker than at the inner ends of
said pieces and about ten per cent. thicker than at the outer ends. The inner ends of
the pieces 15 and 15° are covered with tar paper, or other suitable material, to prevent
a bond with the keystone. The keystone 15 is then cast in position. The center of
the arch should be elevated slightly above a true center (about one inch to forty feet)
in order that it may form a true are of a circle after the bridge is completed and
settled. The false work used in casting the arch should be left in position about
twenty days after the arch is closed, or long enough to allow the concrete to set.
I omit the usual haunchings on top of the arch and in their place I insert concrete
walls 16, in the form of right angled triangles. The short side of the triangle resta
against the vertical face of the abutment and the hypotenuse rests upon the upper
surface of the arch, thus bringing the long side of the right angle in a horizontal
plane for the purpose of forming ribs to support the superstructure of the bridge.
Similar walls 17 join with the wing walls and the edges of the arch. There is no
bond between the walls 16 and 17 and the arch. The space between these walls is
filled with clean clay and rammed solid, after which the side-walks and road bed is laid
in the usual way.
Several coats of plastering are applied to the face of the arch and the wing walls,
the finishing coat showing an imitation of alternate sinooth and rockface stonework.
The distinguishing feature of my concrete arch bridge is the joints in the arch and
the substitution of the walls 16 and 17 for the usual haunchings, thus leaving the
pieces of the arch free to expand or contract without cracking or breaking the arch
and will also allow a settlement of the support of the arch without cracking the
arch.
Where it is desired to build a bridge using a span or spans of from twenty to
fifty feet in length, the form of arch just described and shown in detail in Fig. 1 is
sufficient and will prove very strong and durable.
The layer of tar paper between the ends of the arch and the skewbacks forms a
joint between the arch and the abutments which allows of sufficient action caused by
expansion or contraction without cramping the parts of the arch and cracking or
breaking the arch and abutments.
When it is desired to build an arch for a span of from fifty to one hundred feet, the
arch is constructed as shown in detail in Fig. 4. A layer of white lead or asphalt 18
is inserted between each end of the arch and the skew backs, and a similar layer is
inserted on each side of the keystone. The layers 18 should be at least an inch thick
and in other re-pects the construction of the arch is similar to that already described.
When it is desired to build a span of from one hundred to three hundred feet, I
employ the construction shown in detail in Fig. 5. In place of the layers of white
lead or asphalt, shown in Fig. 4, I now employ iron shoes 19 having joints 20 in
their center and the faces 21 on each end. One end of the shoe rests upon the surface
of the skew backs and the lower end of the arch rests upon the other surface, thus
forming a hinge joint between the arch and the skewbacks. A similar shoe is inserted
between the upper end of the segments of the arch and the keystone. The shoes 19
extend the whole width of the bridge, as do the layers of tar paper, or white lead or
asphalt, as heretofore described, and form supports for the arch and allow of its moving
by expansion or contraction without injuring the pieces of which the arch is composed
and without breaking or cracking any part of the bridge. This construction also
allows the foundation to settle without showing any cracks.
Thus it will be seen that by adopting my invention a concrete arch bridge may
be built having spans any where from twenty to three hundred feet in length which
could not be done by any known old process.
A complete arch constructed in accordance with my invention herein described
comprises three pieces and four joints. Each of the three pieces are cast in position
as heretofore suggested. In making these castings, the section to be constructed is
subdivided to suit the exigiencies of the case. After work commences on one of these
subdivisions, that subdivision must be finished before the work is discontinued for the

page_text: noon hour or for the night, in order that there may be no divisions or cracks in the
subdivision caused by the hardening of one part of the concrete before the next part
is added. When the subdivision is completed, the templets in which the subdivision
has been cast, are left in position until the workmen are ready to begin the next
subdivision; then the templets are removed and the exposed surface of the completed:
subdivision to which it is proposed to join the new subdivision is thoroughly
scratched by an iron brush and cleaned off with water, and a thick coat of mortar
is spread all over said surface in order to prepare it for taking a bond with the:
completed subdivision, and this process is repeated until the entire section is
completed.
In constructing an arch as hereinbefore described, I use concrete prepared as
follows: Take one part of Portland cement, three parts of sand and five parts of
macadam by measurement; mix the sand and cement thoroughly together while
dry, then add a good sprinkling of water, mix again until a stiff mortar is formed,
then spread the macadam all over the mortar and turn the whole mass over three or
more times until the spawls are all covered with mortar. Then place the concrete
so formed immediately in position and rain the same until the water flushes to the
surface, after which the concrete is not to bo disturbed. In order not to disturb the
newly made subdivision of the section by expansion of the false work from
the moisture or dampness of the fresh concrete which is to form the next adjacent
subdivision, the false work is thoroughly soaked for at least two days before the
concrete work commences, and then the sheeting of the false work is covered with
water-proof paper so that no additional moisture can come in contact with said false
work.
An arch consisting of only three members constructed in accordance with my
invention is strong enough to carry almost any weight, and supplemental haunches,
which are a matter of necessity for either stone or brick arches, are not required in
my bridge. This omission takes a large weight off the foundations of the bridge, or,
in other words, the foundations for an arch of my construction do not need to be near
as heavy as for the old style stone or iron arch.
In the place of the usual supplemental haunches I make the arch thicker at the
breaking point, which is about one-third of the length of the span from the skew-
hacks, and from the breaking point the segments of the arch taper both ways, being
the thinnest at the point next the keystone. The walls 16 are not a necessary part
of the arch, but may be inserted or left out, as desired. When inserted, these walls
form a convenient and effective support for the roadway, sidewalks, or whatever
superstructure there may be above the arch.
Having now particularly described and ascertained the nature of my said invon-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. A concrete bridge consisting of abutments, the haunches comprising voussoirs
of concrete bonded together, said haunches being unbonded to the abutments and to
each other, substantially as specifiod.
2. A concrete bridge, consisting of abutments, launches comprising voussoirs of
concrete bonded together, said haunches being unbonded to the abutments, and a
keystone, said keystone being unbonded to said haunches, substantially as specified.
3. A concrete bridge consisting of abutments, the haunches comprising voussoirs
of concrete bonded. together, said launches being unbonded to the abutments, a
keystone, said keystone being unbonded to said haunches, and walls on top of said
haunches, said walls being unbonded to said haunches and to said abutments,
substantially as specified.
4. In a concrete bridge, metallic shoes jointed together and inserted between the
ends of the haunches and the skewbacks and between the opposite ends of the
haunches and the keystone, substantially as specified.
5. A concrete bridge consisting of abutments, haunches comprising voussoirs of
concrete bonded together and cushions of asphalt or white lead inserted between the

page_text: adjacent faces of said haunches and the skewbacks of the abutments and between
the meeting faces of said haunches, substantially as specified.
6. A concrete bridge consisting of abutments, haunches comprising voussoirs of
concrete honded together and cushions of asphalt or white lead inserted between the
adjacent faces of said haunches and the skewbacks of the abutments and between
said haunches and the keystone, substantially as specified.
7. A concrete bridge consisting of abutments having skewbacks, cushions of
asphalt or white lead upon said skewbacks, haunches comprising voussoirs of
concrete bonded together, resting upon said cushions, cushions of white lead or
asphalt upon the upper ends of said haunches and the keystone resting between said
upper cushions, substantially as specified.
8. A concrete bridge consisting of abutments having skewbacks, cushions of
asphalt or white lead upon said skewbacks, haunches, comprising voussoirs of
concrete bonded together, resting upon said cushions, cushions of white lead or
asphalt upon the upper ends of said haunches, the keystone resting between said
upper cushions, and walls on top of said haunches, said walls being unbonded to said
shaunches and to said abutments, substantially as specified.
9. A concrete bridge consisting of abutments having skewbacks, metallic shoes
resting upon said skewbacks, mating metallic shoes jointed to said first mentioned
shoes, haunches comprising voussoirs of concrete bonded together resting in said
second mentioned metallic shoes, metallic shoes at the upper ends of said haunches
and metallic shoes jointed to the last mentioned shoes, and a keystone resting
between said last mentioned shoes, substantially as specified.
10. A concrete bridge consisting of abutments having skewbacks, metallic shoes
resting upon said skewbacks, mating metallic shoes jointed to said first mentioned
shoes, haunches comprising voussoirs of concrete bonded together resting in said second
mentioned metallic shoes, metallic shoes at the upper ends of said haunches, and
metallic shoes jointed to the last mentioned shoes, a keystone resting between said
last mentioned shoes, and walls on top of said haunches, said walls being unbonded
from said haunches and said abutments, substantially as specified.
Dated this 10th day of August 1896.
GEORGE ADAM GEISEL.