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In the last issue of this newsletter, we featured an extensive project
which we were working on at the time: architectural ornamentation for
the Great Platte River Road Archway Monument. The project was recently
completed and shipped to the midwest for installation. Stretching across
Interstate 80 in Kearney, Nebraska, this new 309-foot-long archway honors
the pioneers who, 150 years ago, traveled west on the Great Platte River
Road. The Interstate now follows the same route.
Welding Works'
role in this ambitious undertaking was the fabrication of the symbolic
exterior ornamentation for the structure. Designed by Kent Bloomer,
the ornamentation includes two sets of 27-foot-high aluminum wings which
are mounted atop the north and south towers of the Archway. Wings were
chosen by Bloomer to symbolize movement, transportation and communication.
Bloomer also designed a 309-foot trellis to span the length of the archway.
Its braided wave style evokes the feeling of the Platte River. Completing
the ornamentation is its centerpiece, an intricately-detailed aluminum
horse, representing the Pony Express, that leaps out of one set of wings.
In all, approximately
12 tons of fabricated aluminum plate, sheet, pipe and structurals were
used in this project, along with 6 tons of support steel and stainless
hardware. All aluminum plate ornaments were cleaned and left in their
natural finish. They were fabricated in pieces as large as possible
to expedite final on-site assembly.
Walter P. Camp,
Vice President, negotiated the contract for the work with Bloomer and
originally developed the scope of the work. Price van der Swaagh, President,
served as the central clearinghouse for all the information from the
ornamenter, engineer, contractor, inspector and trucker involved in
the project. Van der Swaagh was actively involved in the daily problems
that arose and was out on the floor working them out.
During the engineering
and design phase of the project, the design of the wings was the first
and most important step. However, each pair of wings needed an independent
structure behind it for support and to allow the interfacing of the
artwork to itself and to the steel structure on the building. The design
of these structures was the responsibility of Doug Rutledge, Project
Engineer at K L & A (structural engineer for the project), who supplied
rough sketches of the support structure. As complete as they were, there
were countless challenges facing Welding Works as they sought to marry
the artwork to the structure. Communication between us and the design
engineers was ongoing, and the design engineers also made several on-site
visits to our facility.
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Over
400 pieces of aluminum give detail to the horse's skin. |
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North
tower and trellis. |
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The welding for
the project was done exclusively with the GMAW process. Welding Works
certified procedures, as well as eight welders, to AWS standards for
5052-H32 and 6061-T6 aluminum material.
Cutting was accomplished
by conventional band saw for the structural shapes (beams, angles, structural
tubing, etc.). The plate shapes, which comprised the majority of the
feathers and tendrils, were cut on an optic-eye burning machine. This
machine has the capacity of cutting 6 feet wide by 16 feet long sections.
The shapes were taken from eighth scale and quarter scale models and
blown up to full-scale flat patterns. These patterns were then made
into black-on-white templates, so that the optic-eye tracer could follow
the shapes. An operator was thus able to cut a multitude of varied shapes
with speed and accuracy.
Forming presented
a considerable challenge. The models were the source of information
regarding how much the elements were to be formed. Bloomer's studio
scaled the models and developed rolling and forming templates for Welding
Works to use. A trial and error method was generally employed in arriving
at the finished look of each shape. Once the shape was developed, Welding
Works used a press brake, as well as two rolling machines.
The horse was the
most time-consuming element of the sculpture, due to the many pieces
requiring hand forming. Measuring 14 feet high by 4 feet wide by 17
feet long, its intricate frame is comprised of over 300 aluminum plates
of 1/4" and 1/2" thickness that are welded to three main support
plates. Over 400 pieces of .090 aluminum were hand-cut and fitted into
place to give detail and texture to the skin. After the skin was tacked,
all seams were fully welded.
The supports for
the horse were critical the horse had to appear as if it were
standing on its hind legs, without any visible support structure. Two
external supports were camouflaged by the mane and tail.
In addition, Welding
Works completed the trellis that now stretches across the length of
the Archway, a process that required hand-feeding 1700 feet of aluminum
pipe into an hydraulic pipe bender. The trellis consists of 16 sections,
each requiring multiple and differing radii.
In order to ensure
the artwork's fit on the Archway, and to develop the struts that hold
the artwork, full-scale mock-ups were required for both the north and
south towers of the building. A survey of the building was taken and
used to develop pedestals that represented the building pedestals. The
steel support system was erected in Welding Works' yard. The data to
place the foliage were developed from a survey of the building that
was taken on the roof in Nebraska. The artwork was then laid out and
supported in its proper relationship to the building and to itself.
Struts were then developed to hold all the foliage.
Simulations of
the existing conditions at the site and test-assembly were especially
important. Due to the complexity and the irregular shapes, Welding Works
had to make sure that all assemblies fit together and would erect without
any interference. The structural engineer was able to clarify many items
that were impossible to calculate on paper. The test-assembly also enabled
Kent Bloomer to view the completed ornaments and determine if the artistic
criteria had been met. In short, it gave all parties concerned a sense
of security, knowing that any problems would be worked out at Welding
Works before shipment.
After test-assembly
at Welding Works, the ornamentation was delivered to Nebraska. It took
five oversized truckloads to transport the project to the site. Now
that it is installed on the Great Platte River Road Archway Monument,
it helps to welcome visitors to two levels of interactive exhibits,
housed within the Archway, which make the Wells Fargo Stagecoach and
the Pony Express "come alive".
Welding
Works won a NOMMA award for this project. |