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Canyon Bridge Rehab - Second Truss Back on River

Jeffersonville, August 3, 2004 - Preparations began about 7:30 in the morning. By eleven o'clock, the second truss had been replaced over the Brewster River.
      As done with the first truss, an I-beam with slings was prepared to lift the truss by the bottom chords. While the truss is being raised to an upright position, its structure can flex. Because the diagonal braces are held in place by the dead-load of the structure when standing, if the loading is released the braces can move in their seats. To correct this, the truss is raised to an upright position, set on blocks and held there while the braces are driven back into place.
       The truss is returned to the abutments and braced to its mate with temporary tie-beams. Next, the floor and roof systems will be put back, followed by new roofing and siding.
Canyon Bridge. Photo by Joe Nelson, August 3, 2004 Canyon Bridge. Photo by Joe Nelson, August 3, 2004
Preparing the truss for lifting.
Photo by Joe Nelson, August 3, 2004
The two "end" floor beams are located where the Burr arch meets the chord, so the arch planks here are ported to receive them; the ports on the second truss need to be threaded onto these two floor beams. Photo by Joe Nelson, August 3, 2004
Canyon Bridge. Photo by Joe Nelson, August 3, 2004 Canyon Bridge. Photo by Joe Nelson, August 3, 2004
Going up. Notice the flex in the truss.
Photo by Joe Nelson, August 3, 2004
The truss is set upright on blocks and braced to stand.
Photo by Joe Nelson, August 3, 2004
Canyon Bridge. Photo by Joe Nelson, August 3, 2004 Canyon Bridge. Photo by Joe Nelson, August 3, 2004
Roland Blais drifts the braces into their seats with a mallet called a beadle (pronounced "biddle").
Photo by Joe Nelson, August 3, 2004
The truss is airborne. Note the new members. Most of the original fabric of the truss is preserved.
Photo by Joe Nelson, August 3, 2004
Canyon Bridge. Photo by Joe Nelson, August 3, 2004
The upstream truss is back where the builders had put it some hundred years ago. The first temporary tie beam is in place.
Photo by Joe Nelson, August 3, 2004

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Joe Nelson, P.O Box 267, Jericho, VT 05465-0267
This file posted August 6, 2004