Author Topic: Trout Brook Bridge - Official Work Thread  (Read 26549 times)

Paul Uhland

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Re: Trout Brook Bridge - Official Work Thread
« Reply #375 on: May 28, 2018, 03:08:52 AM »
As Yogi Berra might say..."include me out!"
Paul Uhland

Dwight Winkley

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Re: Trout Brook Bridge - Official Work Thread
« Reply #376 on: May 28, 2018, 06:00:09 PM »
Paul, Only the left (west side) truss is roofed. The right truss, (with the tree)will be roofed next Wed, the 30th. If not finished than on Thursday 31st.

Brendan Barry

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Re: Trout Brook Bridge - Official Work Thread
« Reply #377 on: May 31, 2018, 04:42:24 PM »
Photo update courtesy of Linc Reed-Nickerson. The roof is done on the east truss.














Paul Uhland

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Re: Trout Brook Bridge - Official Work Thread
« Reply #378 on: June 01, 2018, 01:02:47 AM »
Excuse my impatience...both roofs now done. Terrif!  ;D
Also, it's posted that the new bridge will be decked with 3x10s. Sounds heavy.
The original bridge isometric only shows, above the lower main cross members and diagonals,  four courses of longitudinal stringers upon which long ties, then rails, were laid.
What has changed?
Paul Uhland

John Kokas

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Re: Trout Brook Bridge - Official Work Thread
« Reply #379 on: June 01, 2018, 01:09:29 AM »
My guess is lower dead load on the bridge.  Span has been narrowed thus less weight on the span and also smaller train live loads which gives you the ability to add decking load without effecting overall span capacity.  In really basic terms we stripped the car down and if we add a couple of things back, no big deal.....

Mike Fox

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Re: Trout Brook Bridge - Official Work Thread
« Reply #380 on: June 01, 2018, 01:19:53 AM »
Paul,
The cross bracing that is on the joists originally had some beefy longituinal stringers that ran the length of the bridge, something like 8"w X 14"tall. Then the ties sat on those. This made for a very solid bridge.

Our modification, under the approval of the bridge engineer, is to fill in the spaces on top of the joists between the cross bracing. Then lay the track directly on the cross bracing and our new filler blocks. The 3 inch decking will then be laid parralell to the rail for the length of the bridge and approach spans.

This new design accomplishes 2 things. First, the lower height allows the bridge to be installed at current grade height, where to build it as it was would have required raising the roadbed about 2 feet.

Second, the 3 inch decking (was planned originally) will allow our contractor to access the south side of the bridge and make repairs to the grade and haul in material much quicker than we ever could.

Hope that answers your question.
« Last Edit: June 01, 2018, 01:21:30 AM by Mike Fox »
Mike
Doing way too much to list...