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Canoez
11-08-2016, 10:36 AM
http://amazinggracemarina.com/foliageeric.jpg

Gib Etheridge
11-08-2016, 11:13 AM
I always wanted to build one of those. It was a tradition when we lived in New Hampshire to have strawberry shortcake on the local covered bridge on my birthday.

S.V. Airlie
11-08-2016, 11:43 AM
You don't see many of these! The one I'm familiar with is in Sheffield, Mass. Been beautifully restored luckily! Nice picture! More NE than NY.

Canoez
11-08-2016, 11:48 AM
The Cornish-Windsor covered bridge near Mount Ascutney - Photo by Jeffrey Newcomer

http://4.bp.blogspot.com/-Pe0M9et5U54/UYaf5lHjqzI/AAAAAAAAEuc/WOc6Gfo-Btg/s1600/130429CornishWindsorBridgeAcutneyMtPan.jpg

http://mediad.publicbroadcasting.net/p/nhpr/files/styles/x_large/public/201312/IMG_5417.JPG

Jim Bow
11-08-2016, 12:23 PM
Charles Kuralt did a story on the family who built this bridge using hand tools and a team of oxen. The Squam bridge.
https://newengland.com/wp-content/uploads/2013/10/YK0913_059.jpg

Gerarddm
11-08-2016, 12:24 PM
Love 'em all.

Peerie Maa
11-08-2016, 12:29 PM
'taint got no roof, but it is wooden.
https://upload.wikimedia.org/wikipedia/commons/4/47/Mathematical_Bridge_Cambridge.jpg

Canoez
11-08-2016, 12:32 PM
Charles Kuralt did a story on the family who built this bridge using hand tools and a team of oxen. The Squam bridge.
https://newengland.com/wp-content/uploads/2013/10/YK0913_059.jpg

Beautiful...

Canoez
11-08-2016, 12:33 PM
'taint got no roof, but it is wooden.
https://upload.wikimedia.org/wikipedia/commons/4/47/Mathematical_Bridge_Cambridge.jpg

Also beautiful...

David G
11-08-2016, 12:38 PM
There's something primally satisfying about covered bridges. Oregon has a few --

http://activerain.com/image_store/uploads/agents/rickobst/files/2013-12-29%20Wildcat%20Covered%20Bridge%20(11a).jpg


http://www.photographoregon.com/images/Oregon-covered-bridge-shevlin-park.jpg

http://media-cache-ak0.pinimg.com/736x/23/ca/b7/23cab7b819873f5e994c8c973dd519e8.jpg

Canoez
11-08-2016, 12:43 PM
http://cdn3.list25.com/wp-content/uploads/2013/02/24.-Chapel-Bridge.jpg

CWSmith
11-08-2016, 12:44 PM
There's something primally satisfying about covered bridges. Oregon has a few --


http://www.photographoregon.com/images/Oregon-covered-bridge-shevlin-park.jpg



Looks like trout water to me! I like it!

Canoeyawl
11-08-2016, 01:06 PM
This local bridge is all Redwood.
It was completely rebuilt in the mid 1980's using old growth timber.
Evidently the engineering specs vary enough from first growth to demand the original timber, and none of the local mills would, or could, set up their saws for these logs. So a saw was set up on site. These 1st growth redwood logs are very rare...
I transported the wood from a virgin cut up the coast by the Ano Nuevo Ranch to the jobsite. (That was whole different political deal, involving the state of California and the owners of the timberland.) All the logs were well over 8 feet in diameter, the butts over 10 feet. One log per load, 100,000 lbs - it was illegal to transport normally so I did it on Sundays for a month, 4 trips per day, a 10 hour day. Young and dumb.
Local knowledge says the commercial Hwy Patrol doesn't patrol that stretch of coast highway on the weekends, just regular patrols. Fortunately that was true. It was a cat and mouse game with the loggers and the CHP then, and we, the loggers, knew where the man lived and when he was on the road. Commercial cops carry portable scales like bathroom scales right in their vans, and they just park at the top of a convenient grade to listen to your shifting as you come up. They know when you are overloaded! And you are only going about 15-20 mph so they just step out onto the road and flag you over, right there! Back then 5000 lbs overweight could get fines into the $1 per pound range! The trucks have scales built into them.

http://schultzbuildz.com/wp-content/uploads/2015/01/felton.jpg

J P
11-08-2016, 01:43 PM
I have good memories of working on the Town Lattice covered bridge in Quelph, Ontario with the Timber Framers Guild back in '92.

https://s-media-cache-ak0.pinimg.com/736x/a0/b5/94/a0b594fce88c766857ee852741be84fe.jpg

144ft span.

Our crew cut and assembled roof framing components.
https://www.fhwa.dot.gov/publications/research/infrastructure/structures/04098/images/fig212.jpg

All helped raise the lattice side trusses.

https://www.fhwa.dot.gov/publications/research/infrastructure/structures/04098/images/fig214.jpg

Then it was moved by people-power into position by the river where two large hydraulic cranes flew it to its final location on the piers.

Before the crane pick, we were working on the roof shingles and there was threat of rain coming. The engineers did some calculating (as they do) and were concerned that the added weight of the water absorbed by the shingles would put the thing above the capabilities of the cranes. (250 and 300 ton IIRC.) Went without a hitch though and remains one of the most impressive crane jobs I've ever seen. I think some of the shingle work was completed after the bridge was over the river.

amish rob
11-08-2016, 02:21 PM
Wow. One of my favorite threads! Those bridges are beautiful. Thanks.

Peace,
Robert

John of Phoenix
11-08-2016, 02:40 PM
http://cdn3.list25.com/wp-content/uploads/2013/02/24.-Chapel-Bridge.jpg

Lucerne, Switzerland. I've walked that bridge several times.

Canoeyawl
11-08-2016, 02:58 PM
This bridge, not far from the other covered bridge in Felton is still in daily service. They have painted out the "Powder Works" sign.

http://cdn.loc.gov/service/pnp/habshaer/ca/ca3100/ca3169/sheet/00001v.jpg

Canoez
11-08-2016, 02:59 PM
Lucerne, Switzerland. I've walked that bridge several times.

Went there with my parents in the mid 80's. Beautiful city. It was late April and there were boats out on the lake, flowers in bloom everywhere and snow-capped peaks all around. It looked like a postcard.

Canoeyawl
11-08-2016, 03:00 PM
http://2.bp.blogspot.com/-XWEn87k1Nrc/UzY-_p_vETI/AAAAAAAALwI/ghm9S7ytAs8/s3200/_DSC2958.JPG

TomF
11-08-2016, 03:14 PM
Lots of covered bridges here in New Brunswick too - 61 at last count. The longest in the world is in Hartland NB, a nice afternoon drive upriver along the St. John from my home.
http://farm4.static.flickr.com/3164/2637812700_e92b4b381f.jpg

TomF
11-08-2016, 03:27 PM
That's stunning. Thanks Biga.

amish rob
11-08-2016, 03:34 PM
Yeah, biga, that is a beautiful bridge.

As we don't (generally) have them, I wonder, do they build covered bridges because of the snow?

They always remind me of Beetlejuice, which my kids loved. Day. Me say day-ay-ayo.:)

Peace,
Robery

TomF
11-08-2016, 03:37 PM
The protection from the weather helps the bridge deck last a lot longer. And it does shed the snow, though the road on either side still needs to be plowed. :D

J P
11-08-2016, 03:52 PM
http://2.bp.blogspot.com/-XWEn87k1Nrc/UzY-_p_vETI/AAAAAAAALwI/ghm9S7ytAs8/s3200/_DSC2958.JPG

Looks like a Howe truss bridge.
Similar to this rendering of one in Germany but has different roof framing.
One tank at a time.

http://i7.photobucket.com/albums/y279/picsonline/sharemisc/m_covbrdg_zpsrjavyvrs.jpg

Note the shear keys between the doubled deck beams.

Canoez
11-08-2016, 03:58 PM
Draw-bridging the gap.

https://bicycledutch.files.wordpress.com/2012/10/meerwijksebrug1.jpg

Canoez
11-08-2016, 04:00 PM
"living" bridges

http://assets.inhabitat.com/wp-content/blogs.dir/1/files/2009/08/living-root-bridge-cherapunji1.jpg

Todd Bradshaw
11-08-2016, 06:24 PM
Five feet long, HO/00 Scale twin track from little spruce sticks and modeler's plywood.

http://i1303.photobucket.com/albums/ag153/ToddBradshaw/misc%20junk/Bridge002.ajpg_zps7sf5gnk5.jpg

Canoeyawl
11-08-2016, 08:37 PM
Looks like a Howe truss bridge.
Similar to this rendering of one in Germany but has different roof framing.
One tank at a time.

http://i7.photobucket.com/albums/y279/picsonline/sharemisc/m_covbrdg_zpsrjavyvrs.jpg

Note the shear keys between the doubled deck beams.


The Felton Powder Works bridge is a Smith Truss, 1872
http://www.woodcenter.org/docs/dayton-conference/Reckard_Smith's%20Trusses.pdf

Jimmy W
11-08-2016, 09:20 PM
This one is about 10 miles from me. Photos off the web.

https://photos.smugmug.com/Art/Pooles-Mill-Bridge-Park/i-tq8C4j2/0/L/PoolesMillPark%202012%20-%20%2025_HDR-L.jpg

These are both about 30 miles away. The bottom one still gets a lot of auto traffic.

http://pics4.city-data.com/cpicc/cfiles13713.jpg

https://s-media-cache-ak0.pinimg.com/736x/53/d5/d6/53d5d6ec83fbfb7324b6274425d94123.jpg

skuthorp
11-08-2016, 09:33 PM
The mathematical bridge over the Cam (#7) was supposedly originally built without fasteners and stood by it's own math. principles Till the engineering faculty took it apart to see how it worked, and when they put it back they had to use bolts to make it stand. It may be legend of course, but that's what I was told.

amish rob
11-08-2016, 09:50 PM
Went back to look at #7. Reminded me of how much we like our new punt. Wife wants a 20 footer, so next year we'll have to build one.
We have lots of knee deep water around, see.

I love these bridges.

Peace,
Robert

J P
11-08-2016, 09:57 PM
The Felton Powder Works bridge is a Smith Truss, 1872
http://www.woodcenter.org/docs/dayton-conference/Reckard_Smith's%20Trusses.pdf

Yes, I read that re. Smith Truss in your post. Shoulda, coulda worded my comments more better about my perceived similarities of the bridges. Thanks for the link.

seanz
11-08-2016, 10:23 PM
that's canadian engineering for you! those are built by one of my vendors out of a town north of montreal. in that last pic, the trees on the truck are what the glu-lams in the bridge are made from. and that's no ordinary highway truck. since it only runs on their own roads they can run heavy, WAY heavy. if i remember correctly, the truck in that picture has a gross weight of around 300,000 lbs.

Maybe 200000 lbs? Getting a prime mover that's rated for more than 100 metric ton is a challenge. Still, nice load. :)

J P
11-08-2016, 10:53 PM
The mathematical bridge over the Cam (#7) was supposedly originally built without fasteners and stood by it's own math. principles Till the engineering faculty took it apart to see how it worked, and when they put it back they had to use bolts to make it stand. It may be legend of course, but that's what I was told.

Inspired by this thread, I was just perusing an article (Timber Framing #113, Sept. 2014, Phillip C. S. Caston) about the Mathematical Bridge at Cambridge. According to this article the original bridge was built in oak 1748, and was rebuilt in teak 1905. All I can find in the article re. the bolts, was that the rebuild "... is a faithful copy of the original wooden parts, except that the bolts were modernized, so that in effect the original 18th-century design and construction are conserved in their original setting but with younger materials."

Also mentioned is an 'urban myth' that it can be taken apart without taking down the whole bridge. By use of a wooden scale model and a virtual CAD model, the author and his undergraduate student determined that "Most of the pieces could indeed be removed individually, but some required other pieces to be disassembled first. The largest number of pieces that had to be removed, together, however, turned out to be just three." So parts can in fact be repaired piece by piece in situ "... as the legend proposes".

A remarkable work of carpentry, but even more so, the thought behind it.





I always wanted to build one of those. It was a tradition when we lived in New Hampshire to have strawberry shortcake on the local covered bridge on my birthday.

It could be in your blood Gib; the Mathmatical Bridge on the Cam was designed by one William Etheridge.