IMPROVEMENTS IN GIRDERS
Year: 1885

page_text: We, RUDOLPH AUGUST STOFFERT of 4 West Regent Street Glasgow, Contractor
for Iron Work and Fireproof Structures, and THOMAS DYKES of 65 West Regent
Street Glasgow, Architect, do hereby declare the nature of our Invention for
IMPROVEMENTS IN GIRDERS" and in what manner the same is to be performed to
be particularly described and ascertained in and by the following statement:-
"
The present invention is a development of that described in the Specification
accompanying our application for Patent No 1443 of 1885.
In that Specification various modifications of girders are described, embodying as
the leading feature a construction in which an upper and a lower T flange are
connected together by braces of arch and invert form.
In our present invention the upper and lower T flange are retained in the
construction of our improved girder, but the form of the connecting straps or braces
is varied and presents an angular instead of a purely curvilinear outline, the braces
generally forming three sides of a trapezoid or quadrilateral figure whose fourth
side is formed by part of the T flange to which the brace is bolted or secured.
The invention will be readily understood by reference to the accompanying
drawings which show various forins of our improved girders, some adapted to
serve merely as carrying girders and others being employed in combination with
transverse joists of wood or metal.
Figure 1 is a cross section figure 2 is an elevation, and Figure 3 is a plan of one
form of the improved girder. In this construction an upper and a lower flange A A
of T section are connected by straps or braces B which are bolted or rivetted
thereto on opposite sides. Through the openings between or within the braces are
passed the transverse joists C, which may be of wood, steel, or iron and of any
section. The joists C may be fitted in place before securing the top flange in
position or before permanently securing the braces which are adjacent to the joists.
Figure 4 is a cross section of the girder alone, Figure 5 is an elevation of a wooden
joist, C, as cut where it fits the T flanges of the girder and figure 6 illustrates a
mode we may adopt for strengthening the joist C at the cut, and also joining
together the lengths of joists where their ends are butted together.
Figure 7 is an elevation of part of a girder showing the joist C in cross section
with end view of the bearing shoe given in side elevation at figure 8, Figures 8, 9
and 10, are elevations of the joist showing various modes of strengthening the same
at the points where it is cut to fit the webs of the top and bottom flanges of the
girder.
..

page_text: The
Figures 11, 12, 13, 14, 15, 16 and 17, illustrate modifications of girders in which
the connecting braces have their adjacent sides bearing against each other.
transverse joists C, in these examples pass through the braces. Figures 18, 19,
and 20 illustrate examples of carrying girders of construction similar to the
foregoing. The girders shown in side elevation at figures 2, 13, 15, (with joists
removed) may also be used as carrying girders, to take loads on either flange.
Figures 21, 22, 23, and 24 are cross sections illustrating examples of built T flanges
which are connected together by braces of the form described.
Figures 25 and 26 are respectively an elevation and cross section illustrating the
application of cast-steel, cast-iron or malleable cast-iron in the connecting braces,
and flanges.
Such braces lend themselves in a high degree to ornamentation as to form, in
filling and general treatment. At the lines of attachment to, the T flanges and to
each other they may be of any of the forms of the wrought-iron braces illustrated.
The shortest side of the trapezoid may be curved, so that the braces may resemble,
to that extent, the arched and inverted bracing-straps described in our previous
specification hereinbefore referred to. The girder in any of its forms may
obviously be made of curvilinear contour instead of rectilinear, as shown on the
accompanying drawings.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is
A girder composed of an upper and a lower flange of T-shape connected by
straps or braces of the form described and illustrated.