Wow! Just got some photos from the guy that needs a bridge in his back yard. I’ve seen a photo of a 50+ footer using just 2x8s in the Rainbow Bridge website, so it’s possible, but WHEW!
Given the 5′ higher “near” side, I suggested that the first half of the bridge have a raised, flat deck, with the far side curving and following the truss.
Forrest – gotta’ think about this one
Edited 3/12/2008 7:15 am ET by McDesign
Replies
Here are two long ones from the web site, so it can be done . . .
15 meter -
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50 foot -
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Forrest
Edited 3/12/2008 7:26 am ET by McDesign
Forrest,Your thoughts on a flat area at the top make a lot of sense. No use in climbing that much of the hill, twice...Two things... How high does that water come up, in a flood ? To be safe, count on at least twice that...And, how wide are you going to make this ? If as wide as the bottom picture, people are going to be tempted to drive things across it. 3-wheelers, small tractors, etc...
Life doesn't often leave a very easy trail to follow.
Sound like a great project.I will stay tuned. Can it be ordered from a timber frame place?Chuck Slive, work, build, ...better with wood
Looks challenging. I doubt you'll be able to prefab that one.
On second thought, maybe you could, then break it down for transport?
The best reward for a job well done is the opportunity to do another.
I think maybe some of the arches test-assembled here? - should be exciting.
I just finished the second of the nine basement triple windows I'm doing; eating lunch now and will draw on a particular bay window right after.
A lot of yesterday got taken in drafting our town's new planning permit form - my son realized it was weird that I was creating the actual form that I had to fill out and submit as a builder!
Forrest
I'd be afraid it would look unbalanced if the arch wasn't symmetrical. The curved bridges in Venice and one I know of in Cambridge, MA start and end with steps. You could build up a platform with steps on the lower side, essentially a modified abutment, and keep the arch symmetrical.
Whatever you do, wow! I'll keep an eye on this thread.
Cool project. I once saw a tv show on the building of such a bridge with logs somewhere in rural Asia.
I can't tell from the picture, is there rock under there to set footers on?
I got to build a 60' walking bridge back in the early 90s, but it wasn't an arch and it crossed a ravine with only part time water. It was still fun in the woods. I rigged a line way up in two large maple tree, hung a block & tackle from it and was able to set 20' treated 4x12s 15' off the ground in a location I couldn't quite drive to.
"Doubt is not a pleasant condition, but certainty is absurd."
~ Voltaire
There's ledge at least on one side, and a high water mark, according to the owner, who hasn't lived there long.
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Forrest
Edited 3/12/2008 5:27 pm ET by McDesign
Does it take a special permit to build a bridge over a stream of that size? Floodplain permit or?
"Doubt is not a pleasant condition, but certainty is absurd."
~ Voltaire
HEY!!!!
quit mucking up the project....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
LOL
"Doubt is not a pleasant condition, but certainty is absurd."
~ Voltaire
What does he want to cross the bridge? People, bikes, ATV's, cars, what?
jt8
"A single rose can be my garden...a single friend, my world." --Leo Buscaglia
Just people, he says - most of their property is evidently on the other side of the creek. I haven't met with him in person on site yet. Soon.
Forrest
I don't like to be the one to say this but....that's the kind of project that needs a lawyer's advice about liability concerns, specifically how long you'd have to pay premiums, just to protect yourself from potential law suits.
It's along the lines of building a personal airplane of your own design and then selling it. The liability never ceases, no matter who owns it. Even if it's not properly maintained and a natural disaster occurs, they still automatically sue the designer and builder when someone gets hurt.
<that's the kind of project that needs a lawyer's advice >
Absolutely. Before we get to spending money on this, I'll definitely have talk to the lawyer I've used. Maybe even the client I start with next week - he's a corporate RE attorney - I can't afford his rate, but I'll see if he'll throw me a bone.
Forrest
Certainly looks like fun.
I missed my one opportunity at bridge-building, needed to carry loaded concrete trucks. We ran into a major zoning issue, after getting permits from a dozen agencies, state and federal, for the 60' span bridge.
This link is something I'd explore for a pedestrian bridge: http://www.captivecolumn.com/default.htm He mentions one that was built too low, got washed away, basic structure unharmed.PAHS Designer/Builder- Bury it!