Lansing Bridge
by Bonfire Photography
Title
Lansing Bridge
Artist
Bonfire Photography
Medium
Photograph - Prints
Description
This bridge is among the most unusual and significant large scale cantilever truss bridges in the country, on account of its excellent historic integrity, relatively old age, increasing rarity, and unusual design. Located in one of the most beautiful and photogenic settings imaginable, with a small town on the Iowa side, and expansive flood plains on the Wisconsin side, all contained within a large and impressive river valley. There are ample locations to view the bridge from numerous angles, including a truly spectacular and unique view of the bridge from the Mount Hosmer lookout in Lansing, this is a bridge that must be seen in person to be truly appreciated. The bridge has very a very impressive appearance, with well-defined cantilever towers which rise dramatically above the surrounding trusses. The bridge has a camber that is not curved, but is composed of an inclined deck that immediately ends between the cantilever towers at the center of the bridge. The transition is sharp enough that it acts almost like a speed bump, and helps to calm traffic speed on the bridge, increasing the safety of the structure.
Perhaps the bridge's most distinctive and unusual feature is that the central suspended span, which is a Pennsylvania through truss, is not connected to the cantilever arms at the top, and is only connected by the bottom chord and by vertical eye bar suspenders from the top chord. Viewing the bridge from elevation (side view) this unusual design makes the suspended span very easy to discern. The bridge is actually a good teaching tool for demonstrating how a cantilever truss bridge's suspended span is structurally independent from the cantilever arms, in other words, the suspended span it is a complete bridge on its own being held at the ends by the cantilever arms.
The significance of all surviving cantilever truss bridges has risen rapidly in recent years. This is due to the decimation of the nation's historic cantilever truss bridges by short-sighted owners who feel the only solution is to demolish a historic cantilever bridge and replace it with a mundane cable-stayed bridge with no heritage value or engineering significance. The Black Hawk Bridge is a beautiful historic monument that is one of the most defining landmarks and top attractions of the small town of Lansing, Iowa. In addition, the bridge retains excellent historic integrity, is a relatively old surviving large-scale highway cantilever bridge, and has a unique design. Its preservation, whether it continues to serve vehicular traffic or is bypassed by a new bridge and used for non-motorized traffic only, should be pursued at all costs.
The bridge was rehabilitated in 1955. In 2013, additional work took place including a repainting of the bridge. Some of the photos available on this website are from during the repainting.
Uploaded
September 1st, 2013
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