Bridge Building Techniques

[djroggen]

Trying to get some ideas. Clearly the best way to cross a river is through., but for a practice loop, and with depth ranging from 8" deep to 2.5' deep and rushing. It's not practical to cross multiple times. My river area is about 50' across. Curious what you have done/seen done. Thanks to all in advance for your ideas.

[gasgasman]

We use these on our National Forest trails.
http://www.ettechtonics.com/

50' span will run about $100,000.

[Fred1956]

I don't know what you have access to in your area, but we have considered spanning some of our steeper ravines with bridges. One of the things we have discussed using is an old mobile home frame as a base platform then decking it as needed. Just a thought at this time as we haven't actually done it yet. Even old mobile homes were 60' long so a pretty good span could be reached.

[iamovru]

Originally Posted by djroggen

Trying to get some ideas. Clearly the best way to cross a river is through., but for a practice loop, and with depth ranging from 8" deep to 2.5' deep and rushing. It's not practical to cross multiple times. My river area is about 50' across. Curious what you have done/seen done. Thanks to all in advance for your ideas.

This bridge is a work of art. Scroll down to the bottom

http://ktmtalk.com/showthread.php?t=501793&page=3

[swazi_matt]

a few pine trees next to each other - may be a bit bouncy at 50' but good for your balance

[mcnut]

I've built two bridges across the creek that divides our property. One is made from metal trusses from a factory demolition. The other is an old mobile home frame topped with expanded metal.
I'll post a couple pictures later.

[twowheels]

I just helped a guy build a 50 foot bridge across the river that runs through his property.

Cement pylons, two big iron I beams, and 2" rough cut lumber (16' long, most anout 10" wide).

I'll post a pic later.

[bukwheat]

Couple of good size jumps oughta do it....

[mcnut]

[QUOTE=twowheels;147747]I just helped a guy build a 50 foot bridge across the river that runs through his property.

Cement pylons, two .... QUOTE]

It's concrete! Cement is only an ingredient in CONCRETE!
Sorry. It's a pet peeve of mine.

[Boom Boom]

Thread two larger cables thru skids and tie off cable to a tree or large anchor in the ground. Only one bike at a time and keep the travel speed smooth and even or expect to get bounced off it. This was used for years at one of our trials events...first time across was a little interesting. Many places offer skids for free and you can find used crane cable for reasonable cost.