IMPROVEMENTS IN BRIDGES
Year: 1884

page_text: I, JOSEPH ALEXANDER WESTERMAN, of No 5, Via Assorotti Genoa in the
Kingdom of Italy, Engineer, do hereby declare the nature of said invention for
"IMPROVEMENTS IN BRIDGES" to be as follows:-
This invention relates to the construction of bridges suitable for navigable rivers
and whereof one or more span or spans or portion or portions is or are movable
to allow of the passage of vessels when so desired. The object of the present
invention is to construct a bridge of this class in such manner, that the movable
span or spans or portion or portions of the bridge whilst firmly supported shall
at the same time be capable of being readily moved outward or inward to bridge
over the water or to leave an uninterrupted way for the passage of vessels as
the case may be, and this without altering the level of the roadway of the
bridge.
Such a bridge may comprise one or more stationary or fixed spans or portions
supported in any convenient way; a movable span or portion or spans or portions
supported by and able to slide or travel telescopically along and within the stationary
portion or portions, means for operating the same and in connection with the movable
span or portion (or with each where there are several) a rolling or travelling roadway
attached at one end to the movable span or portion; and for the reception of such
rolling or travelling roadway as the travelling span or portion of the bridge to
which it is connected is moved inward; à pit, well, or chamber of any suitable
description.
In one form of such a bridge each fixed span is constructed with two main,
longitudinal girders, with intermediate longitudinal girders conveniently three in
number, the intermediate girders and lower sides of the main girders being con-
nected and braced together by transverse girders in any convenient manner. The
upper sides or ends of the main girders are connected at intervals by transverse
girders or pieces supporting longitudinal girders arranged in the same vertical
planes as the lower intermediate longitudinal girders bereinbefore mentioned. The
movable or travelling spans or portions of the bridge are constructed with
longitudinal girders, suitably connected and braced at top and bottom by
transverse girders or pieces, the bottom members carrying a roadway or footway
or both.
Between the lower longitudinal members of the movable portions of the bridge
and the lower intermediate longitudinal girders of the stationary portions are

page_text: anti friction rollers or wheels, which may be carried by the moveablo portions.
Similar rollers or wheels are provided between the corresponding upper longitudinal
members.
As will be evident a movable span or portion constructed and arranged as
described can be readily moved outward or inward telescope wise within a
stationary span or portion whether loaded or not by means of any suitable
gear such as pinions and racks operated in any convenient manner as by steam,
hydraulic or other power to which end a motor or motors can be arranged within
one or more piers of the bridge.
In order to maintain throughout a practically even roadway or footway, or both
when the movable span, portion or platform is moved outward I employ a flexible
rolling way (road way footway or both) one end of which is secured to the shoro
end of the movablo span or portion of the bridge whilst its other end extends
to the next pier shoreward, or to the shore, if one stationary span or portion
only be employed between the movable span and the shore. It here enters a
pit or well or chamber into which it descends or passes when the movable
span or portion is moved inwards or shorewards and out of which it is again
drawn when the said span or portion is forced outwards, as will be readily
understood.
This flexible rolling way is conveniently formed with a number of metallic
links; joined end to end and having a transverse roller at each joint, an appropriate
number of such rows of links being arranged parallel with each other at suitable
distances apart across the width of the bridge there being secured to these links so
as to extend transversely across the bridge a number of wooden baulks or channel
irons fitted with wooden blocks to form roadway or footway or both. If desired.
the footways may be provided with elastic hand rails that will assume a curved
form when the rolling roadway enters the pit well or chamber mentioned above.
The several rows of rollers attached to the links and carrying the roadway run
upon and are supported by intermediate girders carried by transverse girders which
in turn are carried by the stationary main girders of the bridge.
In bridging over the distance between two stationary portions or piers one
movable span may be employed carried by one of the stationary portions of
the bridge, but I prefer to employ two half spans one carried by each of
two stationary portions situate one at each side of the water way to be
bridged.
For the purpose of supporting the outer end of a movable span or half span
elevated supporting girders carried by and bridging the piers or stationary parts
of the bridge on either side of the waterway may be employed, the movable span
or half span being connected to the said elevated girders by rods, links, or other
convenient means carrying at their upper ends, rollers able to run on the said
girders to reduce friction. Instead of constructing the movable spans or portions
in the form herein before described they may in some cases resemble platforms
provided with flexible ways at their inuer or shore ends and arranged to slide or
move telescopically within stationary portions, which instead of being constructed
of metal girders, may be built of wood, stone or other suitable material.

page_text: I, JOSEPH ALEXANDER WESTERMAN of N° 5 Via Assorotti, Genoa, in the
Kingdom of Italy, Engineer, do hereby declare the nature of my said invention
for IMPROVEMENTS IN BRIDGES" and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
This invention relates to the construction of bridges suitable for navigable rivers
and whereof one or more span or spans or portion or portions is or are movable to
allow of the passage of vessels when so desired. The object of the present inven-
tion is to construct a bridge of this class in such manner that the movable span or
spans or portion or portions of the bridge whilst firmly supported shall at the same
time be capable of being readily moved outward or inward to bridge over the water
or to leave an uninterrupted way for the passage of vessels as the case may be and
this without altering the level of the road way of the bridge.
Such a bridge may comprise one or more stationary or fixed spans or portions
supported in any convenient way, a movable span or portion or spans or portions
supported by and able to slide or travel telescopically along and within the
stationary portion or portions means for operating the same and in connection with
the movable span or portion (or with each where there are several) a rolling or
travelling roadway attached at one end to the movable span or portion and for the
reception of such rolling or travelling roadway as the travelling span or portion of
the bridge, to which it is connected, is moved inward a pit well or chamber of any
suitable description. In one form of such a bridge each fixed span is constructed
with two main longitudinal girders with intermediate longitudinal girders, the
intermediate girders and lower sides of the main girders being connected or
supported and braced together by transverse girders in any convenient manner.
The upper sides or flanges of the main girders are connected at intervals by
transverse girders or connecting pieces supporting longitudinal girders arranged in
the same vertical planes as the lower intermediate longitudinal girders herein.
before mentioned. The movable or travelling portions forming the opening span of
the bridge are constructed with longitudinal girders suitably connected and braced
at top and bottom by transverse girders the bottom members carrying a roadway
or footway or both. Between the lower longitudinal members of the movable
portions of the bridge and the lower intermediate longitudinal girders of the
stationary portions are antifriction rollers or wheels, which may be carried by the
movable portions. Similar rollers or wheels are provided between the corre-
sponding upper longitudinal members.
As will be evident a movable span or portion constructed and arranged as
described can be readily moved outward or inward telescope-wise within a
stationary span or portion whether loaded or not, by means of any suitable gear
such as pinions and racks operated in any convenient manner as by steam,
hydraulic, or other power to which end a motor or motors can be arranged within
one or more piers of the bridge.
In order to maintain throughout a practically even roadway or footway or both,
when the movable span portion or platform is moved outward, I employ a flexible
4

page_text: rolling way (roadway, footway, or both) one end of which is secured to the shoro
end of the movable span or portion of the bridge whilst its other end extends to
the next pier shoreward or to the shore if one stationary span or portion only be
employed between the movable span and the shore. It here enters a pit or well or
chainber into which it descenda or passes when the inovable span or portion is
moved inwards or shorewards and out of which it is again drawn when the said
span or portion is moved outwards as will be readily understood.
This flexible rolling way is conveniently formed with a number of metallic links
joined end to end and having a transverse roller at each joint, an appropriate
number of such rows of links being arranged parallel with each other at suitable
distances apart across the width of the bridge, there being secured to these links
so as to extend transversely accross the bridge a number of wooden baulks or
channel irons fitted with wooden blocks to form a roadway or footway or both. If
desired, the footways may be provided with elastic or flexible hand rails that will
accommodate themselves to the curve or bend when the rolling roadway enters the
pit well or chamber mentioned above-The several rows of rollers attached to the
links and carrying the roadway run upon and are supported by intermediate girders
carried by transverse girders which in turn are carried by the stationary main
girders of the bridge. In bridging over the distance between two stationary
portiona or piers one movable span may be employed carried by one of the
stationary portions of the bridge but I prefer to employ two half spans one carried
by each of the stationary portions situate ono at each side of the waterway to bo
bridged. For the purpose of supporting the outer end of a movable span or half
apan, elevated supporting girders carried by and bridging the piers or stationary
parts of the bridge on either side of the waterway may be employed the movable
span or half span being connected to the said elevated girders by rods links or
other convenient means carrying at their upper ends, rollers able to run on the
said girders to reduce friction. Instead of constructing the movable spans or
portions in the form herein before described they may in some cases resemble
platforms provided with flexible ways at their inner or shore ends and arranged to
slide or move telescopically within stationary portions which instead of being
constructed of metal girders may be built of wood stone or other suitable
material.
And in order that the manner of performing my invention may be fully
understood, I will now more particularly explain the same by reference to the
nccompanying sheet of illustrative drawings whereof Fig 1 is a side view, partly
in section, of a portion of a bridge, according to my invention for spanning a
waterway. Fig 2 is an end view of part of the bridge drawn to a larger scale.
Fig 3 is a transverse section through the fixed and movable spans or portions of
the bridge. Fig 4 is a transverse section through the lower part of a fixed span or
portion and the movable roadway thereon shewing an arrangement of longitudinal
girders to support the rolling way between that part of the bridge to which the
inner end of the movable span extends when moved back or opened and the shore
end. Fig 5 is a longitudinal section of a shore end of a fixed and a movable
portion with attached rolling roadway. Fig 6 is a side view of a modified form
of bridge. Figs 3, 4 and 5 are drawn to a larger scale than the remaining figures.
a, a are fixed spans of the bridge. is a portion of a movable span capable of
sliding telescopically within the stationary span or part. al.
In the drawing it is shown in its outward position to span one half of the
central waterway c, and it is to be understood that the remaining half of the
waterway is to be spanned by a similar movable portion (not shown) capable of
sliding within the other fixed span or part a. The fixed spans a, d may each
comprise two main longitudinal girders d, d, intermediate lower longitudinal
girders c, c, transverse girders of and upper longitudinal girders yg carried by
transverse girders h, h which niso connect the upper sides or ends of the main
girders d, dat intervals.

page_text: Each movable portion or span 6 may comprise three longitudinal main
girders i, with transverse girders j, j for connecting and bracing the main
girders i, i at their top and bottom parts. k, k is a roadway and I, l are footways
carried by the lower transverse girders j. j. m, m, m and m¹, m¹, m¹ are anti-
friction rollers or wheels carried by the movable portion or span b and interposed.
between it and the upper and lower intermediate girders g and e respectively..
m*, m*, are guides for the rollers m¹. n is a flexible rolling roadway and footway
connected at one end to the shore end of the movable portion or span b whilst its
other end extends shoreward to the next pier or shore abutment o. p is a pit, well,"
or chamber in the pier or shore abutment into which the rolling roadway or a
portion of it may pass when the movable portion or span b is moved shorewards
as shown in Fig 5. The portion not shewn of the divided movable span b is to
have connected to it a rolling roadway and footway for which a pit well or chamber
is to be provided.
The pits wells or chambers may be either vertical as shown at p, or inclined as
shown at p when they are formed in the shore abutment. The flexible rolling
way comprises in the example illustrated a number of rows of links q, the links of
each row being connected end to end with a transverse roller q¹ at each joint and
a series of transverse wooden baulks r or channel irons, fitted with wooden blocks,
to form the roadway and footway. 8, 8 are hand rails of elastic material capable
of stretching in order that the roadway may bend and descend into the pit well or
chamber p with its attached footways l, l. t, t are longitudinal girders on which
the rollers q¹ travel. These girders are carried by transverse girders u supported
by the main girders d. The intermediate longitudinal girders e which take the
weight of the movable portion or span 6 when it is drawn in telescopically may be
of a length about equal to that of the said portion b the remaining length of the
fixed span being provided with the longitudinal and transverse girders t, u
respectively.
If desired the flexible rolling. roadway or footway or both may be dispensed
with, the level of the roadway or footway of each movable portion or span being
in this case higher than that of the fixed span.
In this case the shore end of each movable portion or span may be provided with
an inclined plane or planes to render the ascent from one level to the other easy.
The inclined planes may be of metal and be checkered, fluted or otherwise formed
to afford a foothold. It will be noted that the construction shown in Fig 5 which
provides for a movable span extending (when open) to the shore end differs slightly
from that shown in Fig 1 according to which the span al is longer than the part
span b. In Fig 1 the girders g are not at the shore end. In Fig 5 the construction
of the lower part as it would appear in cross section comprises three girders such
as e Fig 3 and between them two smaller girders such as t Fig 4. In the modifica-
tion shown in Fig 6 the outer and free end of each portion b. b¹ of the divided
movable span is suspended by suitable connections v', v' such as rods or links which
depend from carriages or carriers arranged to travel upon elevated supporting
girders carried by piers o¹, o³ on either side of the waterway c. In this case the
parts b, b' of the movable span may be in the form of platforms capable of sliding
or moving telescopically within the fixed spans and be provided with rolling
roadways and footways. In this modified arrangement the upper longitudinal
girders g employed in the previously described arrangement may be dispensed with
as the connections v¹, v¹ and girders v, v will take the unbalanced weight of the
overhanging portions of b, b². A motor or motors of any suitable kind may be
placed in each pier o¹, o¹ for the purpose of moving the movable portions or
spans b, b¹ inward and outward, suitable gearing such as pinions and racks being
provided to impart the necessary movement. This applies also to the arrangement
illustrated in Fig 1.
It will be obvious that the details of construction of the fixed and moveable
spans may be greatly varied according to the circumstances of particular cases.
Also that bridges constructed according to my invention may be employed for
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page_text: spanning spaces other than waterways, as for example, roadways, that require to
be opened at intervals for the passage of traffic of greater height than can pass
beneath the bridge.
"
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. The construction of a bridge with a moveable span or part or parts such as b;
caused to open and close as required by being moved longitudinally within or upon
a stationary span or structure the arrangement being such that when the said
moveable span or part or parts of the bridge is or are in the closed position or only
partly open the unbalanced weight of the overhanging portion or portions thereof
is taken by girders (or a girder) fixed above such moveable span or part or parts
substantially as hereinbefore described.
2. In a bridge constructed with a moveable span or part such as b arranged to
be opened and closed by movement in a longitudinal senso so as when open to be
within or upon a stationary structure or way providing in connection with the
said moveable span or part a rolling or travelling roadway or footway (or a combined
roadway and footway or footways) which when the moveable span or part is in its
outward or closed position will form a continuation of the roadway or footway (or
roadway and footway or footways) of the bridge and when or as the moveable
span or part to which it is connected is opened will enter a pit, well, or chamber
substantially as hereinabove described.
3. The construction and arrangement of a bridge substantially as hereinbefore
described with reference to Figs 1, 2, 3, 4 and 5 of the drawings or as described
with reference to Fig 6.