The designer of this structure appears to have followed Waddell's 1898 prescription of "pin-connected Pratt trusses with parallel top chords and stiff diagonals in panels where stress reversal occurs" for swing spans between 140 and 225 feet. By the early twentieth century the excessive wear at pin-points with swing spans became clear, and so riveted connections became common. The main span here appears to retain its original members except for its power source for turning. It is the only pinned swing span to have survived in Indiana.
The bridge is a full-size truss swing bridge with timber approaches. Most of the mechanics have long been removed, although the roller nest the bridge swung on is still present testifying to this bridge's movable past. Lattice is present on both sides of the top and bottom chords as well as the end posts. V-lacing can be found on the verticals. The structure in pin connected.
Affixed between two timber beam approaches at each end, the rim-bearing, pin-connected Pratt through swing span of twelve panels sits upon its masonry center pier. The endposts and chords are fabricated from latticed reinforced channels. The verticals are also made of laced channels which are heavier toward the center pier. Four die-forged eyebars angle outward from the top most central panel point toward each of the adjacent lower pins on the rim's edge; a pair angles outward from the other top pins and are countered by a pair of adjustable eyebars only in the two panels adjacent to each endpost. Rectangular girder floor-beams support the timber ties and a single track.
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Негізгі бет 130 year old forgotten swing span bridge exploration!
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