Wooden bridge span question

[MikeD74T]

RobA, Have you looked at these bridges? Index A versatile and scaleable bridge design for spans up to 50 feet, build foot bridges, design construction of foot bridges, constructing footbridge design, free bridge design, gartenbrücke, how to build wooden bridge beams, instructions for wooden bridge design, pedestrian arch bridge plans, free plans for garden bridges, pond bridge plans, prefab bridges, rainbow bridge construction technique, the design of foot bridges, vehicular bridge plan, wooden arch bridge design, bach, baupläne, bridge kit, brücke, brückenbauplan sizes required constructing popsiclestick popsicle stick timber footbridge foot bridge fir hemlock cedar pine outdoor pressure treated lumber They have engineered specs & are load upgradable by adding more trusses. MikeD74t

 

[KSopocy]

Just remember your liability goes for scum bag trespassers too,if they get hurt crossing your bridge. Because if it is there, they will cross it by foot, quad, horse, snowmobile and even vehicle if they even think it might hold them. And some, lower than a snake, lawyer will gladly take their case if it is even remotely possible to sue your butt for every dime you have now or ever will have.

Now skip the wood understructure and go get a couple of old I-beam from maybe your county road commission and build your bridge.

Oh, check with your county drain commissioner before you place a bridge over a public drain. The fines and their charge for removing the structure can be astronomical.

Also if you are placing it near any wetlands, you could be going against federal wetland laws. This will surely bring out a tree huggin' bed-wetter or two.

Yes, sir I have been down a few rough roads with this sort stuff.

 

[MAYOR8020]

Any pictures?

yes i will take them today @ lunch and get them posted i dont know if i will have time to get tractor out and on it but ill try
dws

 

[okie350]

Just remember your liability goes for scum bag trespassers too,if they get hurt crossing your bridge. Because if it is there, they will cross it by foot, quad, horse, snowmobile and even vehicle if they even think it might hold them. And some, lower than a snake, lawyer will gladly take their case if it is even remotely possible to sue your butt for every dime you have now or ever will have.

Now skip the wood understructure and go get a couple of old I-beam from maybe your county road commission and build your bridge.

Some of you guys are so paranoid of something happening I dont know you function.

The original poster got some good advice and had a pretty sound plan to begin with. so build it and enjoy it. I'm about to build one myself

 

[chucko]

mboulais

You know that you should double all live loads before doing you math right?
for a horuse I would go more as they "could" be on two feet at any given time

 

[RobA]

You know that you should double all live loads before doing you math right?
for a horuse I would go more as they "could" be on two feet at any given time

I'm not an engineer but I thought to calculate live load I need maximum weight per sqaure foot of bridge. My latest design is 7'x16'. That's 112 square feet. So, 2,000 pounds on 112 sq fet of bridge is less than 20 pounds/sq ft, right?

 

[KSopocy]

Some of you guys are so paranoid of something happening I dont know you function.

The original poster got some good advice and had a pretty sound plan to begin with. so build it and enjoy it. I'm about to build one myself

Okie350,

I'm not paranoid. Just have seen the lawsuit happen in person. It was not a pleasant experience.

KSopocy

 

[chucko]

20 pounds/sq ft is more like a roof live load.(not total load)
Building I just did had a deck on the roof that area was 100 psf live load + any dead loads (weight of decking ect) and I don't think they were planing on a horse or a ATV on the roof.

Then you have to design hand rails . On a building you have to be able to pust at the top with 200 lbs in any driection. I am willing to be a bridge is much more in all cases

 

[Danno1]

.

Rob,

The horse is not spread out over the whole bridge. If he's on two feet that's what's called a point load. Or two point loads actually. Do a Google for "Beam calculations".

Simply Supported Beam Loading Options

.

 

[scgargoyle]

I've built one of the bridges suggested by MikeD74T. The website is pacifi.ca.
Very graceful bridges- look through the many pictures. The only problem I had is the the lumber size has to be exact or the drilled holes won't line up. The PT lumber I use was 1/8" oversize, and I had to re-drill the holes.