How to build a bridge over a small creek

[menchhofer]

Since we are do it yourselfers here I thought I would try to get some possible ideas on how to build a bridge over a small creek on my property to facilitate working in the woods with my 1430. I am pretty sure this has not been discussed here. A google search did not provide me with any ideas.

Anyway, I have thought of just finding some old telephone poles and just building the classic homeowner bridge. However, I do not know if this will support the PT.

Does anyone have any ideas, presumably simple, as to how to build such a thing? Thanks

 

[Bob999]

There are differing definitions of "small" but one possibility is to use plastic pipe that is designed to be used under roads. It is available in 12, 18, 24 inch diameter and some larger sizes.

The material is relatively light (as compared to concrete pipe).

A land owner near me used this to bury a several hundred foot section of a small stream to create more usable lawn area.

 

[Code54]

I guess the main question is what is "small", if it is not more than a few feet Rail road ties make a great bridge. Telephone poles will hold a large amount of weight as long as the span is not too great.

 

[tom30519]

Here's a link to radair's well-documented bridge project. His is probably bigger than what you had in mind, but I think the basic idea would scale down pretty well.
Radair's footbrige project

Tom.

 

[stray]

Nice project! One thing I like to do and most I believe on this forum think is to look around and see what is handy. Maybe an old mobile home frame or the like would be a place to start. Good luck on the project and we like pictures.

 

[J_J]

One needs more data to offer any plausible response. Things like length, width, height, what materials do you have available, etc. What is the weight of your PT with the heaviest implement.

 

[menchhofer]

Bridge would need to be about 20 ft in length. About 5-6 ft wide. Sorry for not providing these figures earlier. Pt 1430 as I understand it weighs about 3,000#, plus implement...add another 200 or so.

As far as available construction material I am open to suggestions as the material would need to be purchased.

 

[menchhofer]

On second thought, I believe I would be most comfortable building with wood only even though using an old trailer frame as noted above looked decent also.

I am thinking of 2x12's and building the floor similar to a house. Same basic idea. I am concerned with the span which would be about 15ft with no support.

I liked the idea with the plastic/concrete pipe but I am worried they would become clogged with debris.

As I see it now, I would need to set cement columns/supports similar to the bridge mentioned above (by the way, an excellent bridge) and anchoring the 2x12 "joists onto it.

 

[J_J]

Here are some recommendations that I have. If you are trying to cover 20 ft , set five pairs of dock building post 5 ft apart . Bolt two 2X12 to each post, that way, your deck will be sitting on 4 2X12's Set the width of the post and 2X12 to match your tires on the PT. Top of the bridge could be 4X6, railroad ties, 2X12, etc. You would build it like a dock on the river, but stronger. If you were any good at cement, you could use cement and rebar to make a really nice bridge, by forming up 8 in by 8 in square, and about 26 ft long, with 5 to 6 rebars running the full length. You would set the cement post in the ground and/or water, and rent a crane for a day and set the long rails on the post tying everything together.

They might move these post into building projects.

 

[ontheweb]

</font><font color="blueclass=small">( Bridge would need to be about 20 ft in length. About 5-6 ft wide. As far as available construction material I am open to suggestions as the material would need to be purchased. )</font>

Here's a great option. This guy makes these wooden bridge kits you can assemble or you can cut and build your own. Plans are only about $25, and he will custom-design to your specs if an existing plan isn't already there.

Don't underestimate the strength of a wooden bridge. Some of these span 50', and many are made from 2x6's. The design is based on a curved truss which allows the bridge to be lighter, yet equally strong as some straight I-beam bridges that can get very expensive (and bouncy).

If you are handy with a saw, the bridge arches can be built in several days. You can make the bridge as wide as you want by adding more arches.

These bridges require decent concrete footings on each end to handle not just the vertical weight, but also the horizontal pressures. In my opinion, its the most affordable DIY bridge out there. Check out his website, and I have linked an example here where he is driving a tractor across:
http://pacifi.ca/1_24foot.html

Main site & photos:
http://pacifi.ca/photos.html

http://pacifi.ca/images/Chet048.jpg

 

[MossRoad]

There are quite a few threads on bridge building here on TBN in the projects forum and other forums. Just do a quick search on TBN for build AND bridge and start reading.

 

[BillCroasmun]

ontheweb,
Great links, thanks! I have a small ditch/creek I have wanted to build a decorative arched bridge over but figured it wouldn't be sturdy enough for the PT. I have been contemplating making two: one decorative foot bridge and one sturdier tractor bridge in a less visible area. After reading that site a bit I think I can (relatively) inexpensively build one bridge for both purposes. /forums/images/graemlins/laugh.gif

 

[redsox2004]

Hi,

I am looking to also build a wooden bridge across a 20' creek that has different levels on the sides. The bridge needs to be 6' wide, over 20' long (creek bed is 20') and able to handle at least 2,500 tractor.
I was thinking of using 4x6 posts buried in 12"x4' deep concrete sonotubes. There would be 3 sets of 3, center of bed and near the two banks. I was hoping that two 2x12's would make a strong enough beam and space them at 16" on center. I would carraige bolt the two 2x12's that are are either side of the 4x6 posts and lay the 2x12 joists on top of them and screw 2x6 on top for the decking. I know there is more to it then this so I am looking for some advise. It is in Michigen so I have a 42" frost line. Also, this is only an active creek in the spring and fall, it is dry right now. the creek is roughly 1,000 feet from the road so having trucks for concrete or a crane is out of the question, this has to be done by hand. I also need to be careful because the creek is only 14" to 3' deep. I am also concerned that the low side will be under water in a big flood that happens maybe once every 5 years. Oh one other thing, the span for the double 2x12's would not be more then 8' due to the pilliers and 2x12's bolted on the sides of them.
So there you have the info, mindset and challanges, any ideas?

 

[sldva00]

The following link is to a bridge made by a TBNer. Don't know if it will meet your needs, but it was well built.

http://www.tractorbynet.com/forums/build-yourself/171787-another-bridge.html

 

[rekees4300]

I am pretty sure this has not been discussed here. A google search did not provide me with any ideas.

There are several threads at TBN discussing this topic. Instead of Google search, use the TBN Search function, enter "bridge" as a keyword and select "Search Titles Only"

 

[Bob999]

Have you considered using PVC conduit. It is available in 20' lengths and diameters up to 2' or more. Two or more lengths side by side are used where there are large flows.

The conduit is simply laid in the stream bed and covered with soil. So far as I know the life time is unlimited and there is very substantial load carring ability--it is used for drainage under public roads.

 

[pajoube]

Bridge would need to be about 20 ft in length. About 5-6 ft wide. Sorry for not providing these figures earlier. Pt 1430 as I understand it weighs about 3,000#, plus implement...add another 200 or so.

As far as available construction material I am open to suggestions as the material would need to be purchased.

Get a flat bed trailer that has been damaged (undercarriage), this will give you the length, width, and strength you need. Just set on cement pilings on both ends.
PJ

 

[KeithT]

find an old mobile home. The steel beams are very stout.

 

[MossRoad]

Hi,

I am looking to also build a wooden bridge across a 20' creek that has different levels on the sides. The bridge needs to be 6' wide, over 20' long (creek bed is 20') and able to handle at least 2,500 tractor.
I was thinking of using 4x6 posts buried in 12"x4' deep concrete sonotubes. There would be 3 sets of 3, center of bed and near the two banks. I was hoping that two 2x12's would make a strong enough beam and space them at 16" on center. I would carraige bolt the two 2x12's that are are either side of the 4x6 posts and lay the 2x12 joists on top of them and screw 2x6 on top for the decking. I know there is more to it then this so I am looking for some advise. It is in Michigen so I have a 42" frost line. Also, this is only an active creek in the spring and fall, it is dry right now. the creek is roughly 1,000 feet from the road so having trucks for concrete or a crane is out of the question, this has to be done by hand. I also need to be careful because the creek is only 14" to 3' deep. I am also concerned that the low side will be under water in a big flood that happens maybe once every 5 years. Oh one other thing, the span for the double 2x12's would not be more then 8' due to the pilliers and 2x12's bolted on the sides of them.
So there you have the info, mindset and challanges, any ideas?

I would not encase wood into cement. If something happens to the wood, the whole pier is ruined forever and eternity. Instead, build the cement pier to the proper height in the first place to lay the bridge on top of it OR put anchor bolts into the top of the pier and use steel plates to bolt the wooden legs to the cement pier.

Also, consider strongly the option Pajoube offered regarding finding an old flatbed trailer to use. That way, all you will have to do is put in concrete piers on either side of the creek at the proper locations and set the flatbed on top of the piers. DONE! Simple as that. :thumbsup:

 

[SpringHollow]

Encasing wood in cement speeds up the decay.

Ken