The Forestry Forum

General Forestry => Forestry and Logging => Topic started by: KyLogger on September 09, 2012, 05:36:24 PM

Title: Bridge Construction
Post by: KyLogger on September 09, 2012, 05:36:24 PM
Hey guys! Went today and looked at a small 22 acre boundary of pretty good timber. Shot the guy a price and got it (pending signing of the contract etc...) The only problem I have to contend with is a narrow (10' top of bank to top of bank) and deep (8') with only 4" of water in the bottom that has to be crossed with the log truck. Previously there were three culverts and fill, but that washed out a few years ago. I need to get across but culverts are pricey and it would require a lot of fill. I was considering using timber on site to make a timber bridge i.e. hemlock logs with 2" oak decking spiked down. The bridge is to stay in place and the owner will cover half the cost. I cannot find a semi local source for the square portable timber bridges (or know an approximate cost) Have had no luck finding a trailer frame etc......

Any Ideas? Would my log and decking idea hold up to a single axle with up to 3,000 bdft (int. scale) And what kind of abutments would I have to use, if any? My available equipment consists of a 450 JD dozer, my cable skidder and a loader tractor (forks no bucket)........................


Tom
Title: Re: Bridge Construction
Post by: John Mc on September 09, 2012, 07:21:15 PM
A few years ago, the state of Vermont's  had a program to educate loggers, foresters and landowners about portable skidder bridges.  This may not fit your needs, since it appears you are looking for a permanent bridge, but maybe it will spark some ideas...

Here's a link to a portable skidder bridge brochure (http://www.vtfpr.org/watershed/portbridgebroc.cfm) they were handing out.

Here's a link to a page with more info, including links to plans, and materials and spec sheet, as well as a YouTube video.
     
www.vtfpr.org/watershed/initiative.cfm (http://www.vtfpr.org/watershed/initiative.cfm)

The bridges are designed to handle up to a 14 foot clear span, and are relatively simple to make.

Hope some of this helps.
Title: Re: Bridge Construction
Post by: bill m on September 09, 2012, 07:33:47 PM
If this bridge is to stay in place it should by steel. Also because it will be permanent the local conservation commission must be notified.
Title: Re: Bridge Construction
Post by: thurlow on September 09, 2012, 07:40:31 PM
Around 'here', salvaged railroad tank cars.......with ends already removed........can be bought cheaper than culverts or bridges;  been a while, so I don't know current prices.
Title: Re: Bridge Construction
Post by: John Mc on September 09, 2012, 07:46:05 PM
... Also because it will be permanent the local conservation commission must be notified.

The regulations regarding that will vary by state.  No local notification requirement here.
Title: Re: Bridge Construction
Post by: Autocar on September 09, 2012, 08:31:16 PM
I'll second the rail road tanker farmers use them around here all the time but I have no idea on what they cost or while they get them.
Title: Re: Bridge Construction
Post by: beenthere on September 09, 2012, 09:06:24 PM
Where did the culverts end up that washed out? Completely gone or just not usable?

Seems another culvert with a waterway for the occasional flood water to flow around the bridge rather than wash it out, would be the cheapest way.
Title: Re: Bridge Construction
Post by: Stephen1 on September 09, 2012, 09:18:15 PM
A few years ago, the state of Vermont's  had a program to educate loggers, foresters and landowners about portable skidder bridges.  This may not fit your needs, since it appears you are looking for a permanent bridge, but maybe it will spark some ideas...

Here's a link to a portable skidder bridge brochure (http://www.vtfpr.org/watershed/portbridgebroc.cfm) they were handing out.
   
I like this, I am thinking it would work great for a permanent bridge, for my tractor in my Sugar Bush. I could build it suit my creek, and tractor.
Title: Re: Bridge Construction
Post by: Decked on September 09, 2012, 09:22:53 PM
Here's what we use...might give you an idea..

http://admwelding.com/
Title: Re: Bridge Construction
Post by: KyLogger on September 09, 2012, 09:28:39 PM
I have no idea where the old culverts went, that was several years ago. I just talked to my father in law and he has a 20' joint of 42" ADS pipe he said he would let me have. I think that will fit the bill. Drop it in, cut the banks down to fill in and get a load of rock to top it all off. Should do the trick and not be too cost prohibitive. A bridge spanning 10' built outta logs scares me a bit, if it was oak or hickory that would be one thing but I can't be putting marketable timber in for a bridge.  And has anyone got a load of the price of used I beams lately.

I definitely ain't no engineer!!!

Tom
Title: Re: Bridge Construction
Post by: Woodchuck53 on September 10, 2012, 04:13:26 AM
Have you thought about drag line mats? My dad got a pair years ago for a crossing. We put a few 9' cross ties in along both sides of the ditch and pulled the mats across. They lasted for quite a few years.
Title: Re: Bridge Construction
Post by: KyLogger on September 10, 2012, 06:25:17 AM
Yeah I have, and they would be awesome However I cannot seem to find a source for em around here.

Tom
Title: Re: Bridge Construction
Post by: Ed_K on September 10, 2012, 08:13:14 AM
We replaced a 16' span that had two i beams that rotted out,with 7 12"x12"x22' and 3"x 6"x12' hemlock on a back dirt town road.It was designed by an engineer who certified it for 20 yrs.We cover the beams with metal to keep rain off from them and used some pressure treated 2"x12"s to set them on.
Been there 3yrs and many tri-axles and snow plows have been over with no problems.
Title: Re: Bridge Construction
Post by: John Mc on September 10, 2012, 08:42:53 AM
A bridge spanning 10' built outta logs scares me a bit, if it was oak or hickory that would be one thing but I can't be putting marketable timber in for a bridge.

I hear you about not wanting to use marketable logs for this.  Though lots of folks around here are using these portable skidder bridges as the cheapest alternative.  I suppose it makes a difference if you are leaving the bridge behind, vs taking it with you to use on other jobs.  If you take it with you, the cost gets spread out over a lot of jobs.

As far as it holding up to the loads you might run across it... people around here are using them on logging jobs all the time, and they are using the whole 14 foot clear span.  If you have only a 10 foot clear span, you should not be stressing these bridges at the load ratings mentioned on the plans.   

The only problems I've heard are due  old age... eventually, they rot.
Title: Re: Bridge Construction
Post by: John Mc on September 10, 2012, 08:46:46 AM
Using an old railroad tank car for a culvert is a neat idea.

That reminds me of another solution I've seen:  Using an old flatbed semi trailer as a bridge.  Just drag it in across the stream and leave it (the ones I've seen they removed the running gear).

I've also seen an old 20 shipping container used as a bridge.  Makes a good covered bridge, but I'd guess not so great for your application, since getting wide or tall loads through it is not an option.

John Mc
Title: Re: Bridge Construction
Post by: thecfarm on September 10, 2012, 08:52:00 AM
John,no regs in VT about a stream crossing? Not trying to argue with you,but I kinda thought all states had a hisssy fit when even a tree is dropped into any water.
Title: Re: Bridge Construction
Post by: John Mc on September 10, 2012, 09:01:55 AM
John,no regs in VT about a stream crossing? Not trying to argue with you,but I kinda thought all states had a hisssy fit when even a tree is dropped into any water.

Oh, they have quite a fit when you don't follow proper procedures when working around streams. 

What I was responding to was Bill M's statement that "because it will be permanent the local conservation commission must be notified".  I'm sure he's correct about the requirements in his area, but around here there is no LOCAL notification requirement.  My local Conservation Commission would probably wonder why the heck I was bothering them if I came to them with a "notification".  They're good folks, and may have some good suggestions for me, but they don't give any permission for this sort of thing.  I'm not even sure every town HAS a Conservation Commission in VT.

My point was that the regs vary from state to state about what's allowed at all, and who you've got to notify or get permits from.
Title: Re: Bridge Construction
Post by: thecfarm on September 10, 2012, 09:06:46 AM
Now I gotcha. I doubt there is a local one here too,but I would have to go through the state regs on a bridge.
Title: Re: Bridge Construction
Post by: John Mc on September 10, 2012, 10:49:36 AM
BTW... that YouTube video of the portable skidder bridge in my earlier post shows a JD 640 crossing it (at about 2:30 minutes in).  You can't see any flex or sag at all as it crosses.

Towards the end of the video, they mention that 43% of the Vermont loggers who responded to a survey are now using portable skidder bridges.  Even though the survey may not be statistically valid, it's clear that a significant number of loggers are using them.

They use hemlock in the video.  I've been debating about making something similar for a permanent crossing on a seasonal stream in my area (my uses will be much lighter loads - roughly 4000# of tractor with whatever it's pulling).  I have a few black locust trees I was thinking of using... unfortunately, not nearly enough to do the whole bridge. 

I'm interested in seeing what other suggestions crop up here for a low-cost permanent crossing.
Title: Re: Bridge Construction
Post by: logger t on September 10, 2012, 07:01:57 PM
we have used old steel dump truck bodies we cut the sides off and put them in with the skidder and we have used the sides as small skidder briges or for swamp holes just a thought
Title: Re: Bridge Construction
Post by: Maine372 on September 10, 2012, 08:21:43 PM
old highway flatbed trailers work.
old railroad flat cars work.
old platform log bodies work.

start calling truck dismantling places and junk yards around you, somebody has got to have something. hemlock logs for abbutments. pick a tree on the other side of the river to set a pulley up in. run a nice long rope or cable from the bridge to the pulley, then back across the river to a vehicle.

we have used this technique for log bodies and timber bridge panels.
Title: Re: Bridge Construction
Post by: JohnG28 on September 13, 2012, 11:36:15 PM
I have no idea what regulations may be in your area, but knowing just some of the regulations in NY would make me want to find out what is allowable first. From there the most cost effective or just effective bridge can be built.  JMO though.
Title: Re: Bridge Construction
Post by: JoeB on September 14, 2012, 09:06:08 AM
Good Day, another idea that we have used was we demolished an old quarry, and recycled the scale and skelton under neath it. Turned out good as i think it was 53' long. HTH, JoeB
Title: Re: Bridge Construction
Post by: Sixacresand on September 15, 2012, 01:13:36 AM
For a permanent streaming crossing, plastic culverts covered with fill are a good option.  Galvanized will eventually rust and cave in.  Also run a hydrology study to size the pipes to handle the flow including a emergency over flow to handle big storms.  A culvert crossing with fill dirt is the same as the dam of a pond except you are not storing water with a stream crossing.   Bigger  or more pipes may seem like an over kill, but it will prevent an washout during a 50 or 100 year storm.  And do get the blessings from all your environmental agencies. 
Title: Re: Bridge Construction
Post by: KyLogger on September 15, 2012, 06:53:45 AM
I appreciate all the responses! Environmental agencies aren't a concern. I live in E. Ky where there is no zoning, and 1/4 of the "septic systems" are still run "over the hill" ;D  I think that my ADS culvert would be my mist cost effective means. With the price of scrap around here any large piece of metal is either higher than groceries, or already chopped up and gone to the scrap yard.

Tom
Title: Re: Bridge Construction
Post by: Sixacresand on September 15, 2012, 10:02:04 AM
Amen to a "very understanding spouse", KYLogger