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westford2 Back to Front Page.Bid to Rehabilitate The Browns River Bridge Accepted Some Fine Timber Carpentry More Fine Timber Carpentry An Encore in Timber Carpentry Roof Work Begins Abutment Work Starts Roof-work Moves Rapidly Abutment Work Underway The Wing-wall is Poured The Abutments Nearly Ready Bridge Nearly Ready To Move Westford Bridge Back Over River Westford Bridge Dedicated Reported by Phil Pierce Westford, March 29, 2001 - With Renaud Brothers Construction on the job it looks
very much like the old bridge is beginning its final lap on the journey back to its rightful place;
over Browns River where it was built 165 years ago. Work has sterted on Westford's Browns River Covered
Bridge. Notice the "K" frame brace. The gable end sheathing has been removed to access the
upper chord and bracing.→ Scaffolding has been installed to facilitate the replacement
of the upper chord. The internal lateral bracing has been tightened with new wedges. The "K"
frame braces will prevent racking during repairs.
→Westford, Wednesday April 18 - This day found the south side of the roof raised and
the upper chord lifted out and placed on saw horses on the ground beside the bridge. Two
modern-day timber framers, Phil Pellerin and John Ferlin, were hard at work duplicating the
joinery used by the builders of the bridge back in 1838. The original chord is laid beside the new timber while John
Ferland (left) and Phil Pellerin transfer measurements and cut the mortises and splices into the
new chord.
→ The new chord will duplicate the original chord which
consisted of three timbers spliced together. Note the "compression" splice in the end of the new
piece. The splice on the original timber has been cut to reveal the rot in the center.
→ A close-up of the cut away end of the original timber. Holes
drilled by powder-post beetles are evident, some of them indicated by the arrows.
→ In the foreground a new king post is being prepared. The
plywood device perched on the end of the new chord-timber is a pattern used to dimension the
cuts for the joinery. A new tie beam can be seen in the right background.
→Westford, Friday April 27 - A week and one-half has elapsed since the last visit to the site and the cord sections and timbers that were being crafted on the ground next to the bridge had been completed and installed into the truss. The plan had been to move the bridge back to the river in July. The work has been going well enough, it is possible the move may begin in June, Mike Renaud said. The planned repairs to the abutments, which will be subcontracted, still need to be done. The upper chord is in position above the kingposts. The tenons at the top of the kingposts can be seen waiting to be set into the prepared mortises. → The mortise in the chord end is ready to receive the tenon at the top of the end-post. Notice the rafter seats. → A brace is being fitted between a kingpost and a tie beam. The ends of the tie beam are lapped to seat on top of the chord. All of these joints are fastened by mortise and tenon. The timber below the tie beam is temporary bracing. → The chord is now seated onto the kingpost tenons and secured with hardwood pegs, also referred to pins, dowels, or treenails. The cluster of pins in the side of the chord between the leftmost kingposts mark the compression splice joining the chord-members. → The roof system is braced high so the upper chord can be worked on. The crossed members between the tie beams are part of the bridge's lateral bracing system. → Westford, Monday May 7 - With the upper chord work completed on the east side and those new kingposts installed, work has begun on the north side. There, the roof has been lifted to allow the installation of a kingpost and part of the upper chord. The roof is raised and a rotted section of the original chord has been removed. The carpenters are installing a new kingpost. → This view of the installation of a new kingpost shows the lapped lower end of the vertical timber as it is fitted into its recess in the lower chord. Note the vacant bolt-holes in the arch member and in the lower chord. The carpenter's hand grips the top of the post next to the tenon that will fit into the mortise in the bottom of the new chord-section. → The new upper chord section has been readied for lifting into place. Note the large timber below the lower chord. This is a bolster beam. When the bridge is on its abutments, the bolster beam is placed on top of the bed timbers and projects beyond the face of the abutment out over the stream, "bolstering" or reenforcing the parallel chord trusses, shortening the clear-span. → The new upper chord section is fork-lifted into place. → The Upper chord and two new kingposts have been installed on the south side of the bridge. Notice that the braces have been fitted into the seats or steps cut into the top and bottom of each kingpost. Notice the bottom of the right-most post extends beyond the bottom of the lower chord. This is called a knob, necessary on a tension member. The new bolts can be seen at each kingpost station, through the arch-members, lower chord and bolster beam. A new "kick brace" can be seen at the top of the left-most kingpost. → Westford, Monday May 14 - With the roof system back down onto the top chords, work on the roof sheathing begins. Off with the old: making ready for the new roofing. → Stripped of the shingles, light shows through the purlins. → Stripped to the purlins, the roof is prepared for its new covering. → The destination, the north abutment awaits repairs. → Westford, Wednesday May 16 - As the carpenters put the finishing touches on the bridge, work begins on the abutments. The roof is prepared for sheathing while the planking on the portal is renewed. Work continues on the bridge floor system. → Work on the north abutment begins with excavation. → Back view of the excavated abutment. → Westford, Friday May 18 - Almost there! West portal with new sheathing. → A good start with the new 24 gauge sheet- steel standing-seam roofing. → 7:30 a.m. to 10 a.m. → Almost there! → The roof is finished at 2:30 p.m. → Westford, Friday June 1 - Abutment Work Underway! Excavating continues around the broken down-stream wing-wall of the north abutment.→ A piece of the broken concrete wing-wall is hauled aside. → The forms for the new wing-wall footings are under construction. The south abutment is in good shape. According to contractor Mike Renaud, all that is needed there is a new cap. → Westford, Wednesday June 6 - Wing-wall Poured! Hallelujah! The wing-wall footing has been cast and the forms removed. The form for the wing-wall itself is being assembled.→ The wing-wall forms are assembled and nearly ready for the pour. → What we have been waiting for: the Big Pour begins. → Westford, Tuesday June 12 - With the abutments nearly ready the date for the BIG MOVE is soon to be set! The new wing-wall on the north abutment has been cast and the forms removed.→ The forms are prepared for casting the new cap on the south abutment. The north abutment will require a cap as well.→
Joe Nelson, P.O Box 267, Jericho, VT 05465-0267, jcnelson@together.netNo part of this web site may be reproduced without the written permission of Joseph C.
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