Plans for a small bridge?

[Barton]

Where in Georgia are you? There is a pole plant at Sycamore in Turner County right along side I75.

 

[jsborn]

I sincerely appreciate all the help, folks.

Any ideas where to find poles like that in Georgia?

Where in Ga. are you located ? There are several places to buy new poles. The Power companies will usually give you old poles but beware they are either broken (cracked and no longer sound) or rotten. Some times you can find them in good shape but its a crap shoot.

 

[stravis]

I'm in Perry, GA. I actually called an electrician I do business with and he told me I could get the 25' temporary power poles new from Flint Energies for about $75 each. They ought to be perfect for this project. I'm in commercial construction and am about to demo a school starting this summer. I might try to get a couple of smaller beams from the school to use as support as well. That's a good idea.

In fact, there is another area on the land that I intend to build a bridge, but it is a much longer span. If I can score some longer steel beams that would be a great place for them.

 

[spo307]

Heres the bridge I built on my property last fall. I made it out of used T-Bar joist I primed and painted.

Nice job, i need to span 33 feet, and get the tractor across w/ BH #7500

 

[scoutcub]

Same boat here (haha) need to span a small creek on the property. Was thinking of digging out bunkers and laying 8 or so 12"+ logs from the property across, then decking.....any thoughts?

 

[Ridgewalker]

Same boat here (haha) need to span a small creek on the property. Was thinking of digging out bunkers and laying 8 or so 12"+ logs from the property across, then decking.....any thoughts?

Scroll back up a few posts and check out the "timber bridge" link. That link has some great info on what you are asking about.

 

[rambler]

Nice job, i need to span 33 feet, and get the tractor across w/ BH #7500

You need an engineer. That span is nothing to fool with. Takes some real material.

I always like steel. It doesn't rot in 10 years.......

--->Paul

 

[scoutcub]

Scroll back up a few posts and check out the "timber bridge" link. That link has some great info on what you are asking about.

OK got it, that's exactly what I need. Now I just have to figure out log diameter X # of logs X span = weight bearing ability....?

 

[eepete]

Years back I was looking at the equation for the deflection of a beam from a point load at some point on the beam. There were various constants that dealt with the material dimensions and type. What was interesting was there was a fifth power term in there that had the length of the beam. In computer code terms, it was a L ^ 5 or length to the fifth power.

So part of why it's so hard to apply common sense to spans is that this fifth power term puts it way outside of most of the things we see. As an example, when going from a 20' to a 25' span, the deflection at the midpoint goes up by a factor of 3 even though the length only went up by 25% or a fourth.

So I'm with rambler on this one.

Pete

 

[spo307]

You need an engineer. That span is nothing to fool with. Takes some real material.

I always like steel. It doesn't rot in 10 years.......

--->Paul

yes 2 w 12 beams 750lbs. each 750 dollars each, was thinking 40 foot flat bed trailer

 

[harwill]

For what it's worth, we made a small bridge about fifteen years ago using two creosoted "switch ties" about 20' long, set on regular ties let into the bank. Rebar pins held it together and it was planked with treated 2x8 pine. Still driving 3/4 trucks over it today. Almost had a heart attack when we found out the VFD had driven a tanker over it to reach water and then came back loaded!
Ties come in different sizes according to usage. Get the bigger ones.

 

[RxRatedZ71]

I built a wooden bridge across my "feeder stream" finger last summer. It spans about 22ft. I managed to snag 4 electric poles from a guy on Craigslist who only lived about 15 miles away, who delivered them for $100. They were about 16-20" diam at the butt-end and about 30' long. I just wanted to be able to drive my Polaris Sportsman over the bridge to my future barn-site, so I elected to only use 2 poles (the other 2 are currently being used to build a foot-bridge over my main creek). I spanned them about 4' apart to match up with the vehicle width. I decked the bridge with PT 2x8s and used counter-sunk lag-bolts to secure them to the bridge beams. I secured the beams to the banks by burying them about 15 inches down. I dug a trench under the end of each pole and filled it with several sacks of quick-crete and then ran some re-bar through the utility holes of the power poles. On either side if the bridge I secured PT 4x4x12' posts into the creek-bed then ran lateral supports the either side with PT 2x12s. This all me be over-kill for only needing to support a 800lb ATV but I bet it might support significantly more. I've debated whether to drive my JD tractor over it, but as my wife puts it, " Your not driving that tractor over anything that YOU built, at least while we're still making payments on it!"

 

[Bartcephus]

At my hunting lease, we have two bridges built using power poles as main beams. I was leary of them at first but after seeing the others drive their big tractors and big trucks over the bridges, I am quite impressed. The bridges span over quite a drop. Lately however, I have one bridge which I avoid now because the washout is removing the soil beneath one side of it. They have been there for several years and have held up well. Just a little concerning now...

 

[RxRatedZ71]

Okay, so I snuck away this afternoon to take some pics of my bridge. The first shows the decking and overall length. The second is a shot while in the creek-bed showing the power poles which provide the main support.