V.A.O.T. Historic Bridge Committee
Proceedings
Historic Covered Bridge Committee Notes of May 6, 2002 for:
GORHAM COVERED BRIDGE (#4) IN PITTSFORD AND
PROCTOR
Present at Meeting: Committee members J. B. McCarthy, Dave Hoyne, Warren
Tripp, Scott Newman, Nancy Boone and Sue Scribner. Also in attendance were Mr. Ray Beyette
from the Town of Proctor, Jim O'Gorman from the Town of Pittsford, John Weaver representing
the Vermont Covered Bridge Society, Michael Canavan from The Federal Highway
Administration, VTrans project manager Chris Williams and VTrans project engineer Wayne
Symonds.
Project engineer Wayne Symonds prepared a handout clarifying some components of the
Scope of Work for the project previously discussed in January. In addition, Mr. Symonds
prepared a power-point slide presentation to clarify some of the ensuing discussion. The ensuing
notes are to be read in conjunction with the handout as the committee discussion generally
followed the same outline, as follows:
- Roof System - There was discussion relative to knee braces. It is proposed that they
still be replaced, but in the original configuration and size. Intermediate knee braces are proposed
to span from the chord to the rafter sills. It is further proposed that the existing spikes be
replaced with lag bolts as well as any new connection. They will now be in 5-foot increments
instead of the existing 10"-6" increments. No objections were raised by those in attendance.
- Roof Pitch - It was proposed that the existing 5:12 roof pitch be modified to 6:12. If
changed, the center of the roof would be approximately 10 inches higher than at present. This
was proposed in hopes that snow will be shed easier. The designers feel that the appearance of
the bridge will not be noticeably altered. Scott Newman indicated that he would need to consider
this further relative to his responsibilities under Section 106 of the National Historic Preservation
Act and will let the designers know his decision in the next week or so..
- Truss System - Plates on 2 of the splices were removed and it was found that they
were generally in good condition. Therefore, it is not anticipated that many of these members will
need to be replaced or altered. It was suggested that any unspliced lattice members with rotted or
damaged areas would be replaced rather than spliced. It is proposed that eight lattice members at
each end of each truss be replaced with new members of same size but with high grade Southern
Yellow Pine. Other discussion to follow the detail provided in the handout. No objections were
voiced.
Disassembly of the bridge was discussed in light of the extent of repair and/ or replacement of
members. Nancy Boone requested clarification of this. It is not anticipated that every connection
will be taken apart, rather each intact truss will be removed and repaired as well as the chords,
etc. Consideration will be given to adding notes that stress this with follow-up at the pre-
construction conference.
It was proposed that the lower chord be slighter larger than the current configuration as it is
proposed to be glu-lam and the "standardized size" is slightly larger than the existing. No
objections.
- Deck - It is proposed that the deck be 2" x 6" nailed laminated. No objections.
- Floor System - Proposed that glu-laminated Southern Yellow Pine floor beams, 10
1/2" x 13 3/4" in size, be used at 3"-5" spacing. No objections.
- Substructure - Borings have been taken demonstrating that there is very poor soil in
the area of the abutments. Therefore a deep foundation will be needed and it is proposed that
driven piles be used. There will be approximately 25 feet from the top of the footing to the bridge
seat. Use of cast in place concrete is still proposed. The designers proposed either using form
liners to replicate the existing look of the substructure or form the concrete with rough sawn
lumbers. An example of each was shown. It will be left to the towns to decide which is
preferable; it appears that the towns were leaning towards use of form liners and they would
decide the pattern to be used.
Some project details will still need to be clarified by the towns and Scott Newman.
Otherwise, there do not appear to be any areas of controversy and the plan development process
will continue. The efforts by the project engineers to provide comprehensive material for
committee review is again acknowledged and very much appreciated.
Respectfully submitted,
Susan Scribner
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