Just finished a small project and I thought I’d share.

My property has a small creek/seasonal stream. It usually runs from late March to August 1. Not very deep, but if we get a large downpour it can fill the creek. There’s a small bridge that I use to drive my tractor across to mow the field. Last year we got an unusually large downpour and the stream came up over the sides of the bridge. The old bridge consisted of several 6 x 6 posts spanning the creek, with 2 -double thick layers of ¾” plywood. It was 8’ x 8’. It was installed by the previous owner. I moved into my house in 2008. It was starting to show its age, and at a minimum I needed to pull up the plywood and replace that. I also had some concerns I would need to replace the 6 x 6 posts. When the water came up over the sides it also separated the 2 sheets of plywood a little. After the storm I had a gap between the 2 sheets of plywood, and 1 was about an inch lower than the other one.

My dad actually came up with the idea to use an old “flatbed” if I could find one. I kept an eye on Craigslist, and found a really nice one. The seller wanted $500 for it, and I got it for $500 delivered (about 15 miles). It is 12’ x 7.5”. I took my torch and cut off the vertical piece that goes against the cab of the truck. I also had to cut off the rear portion that hung down and housed the tail lights. Washed it down with soap and water to get it ready for paint.


The biggest problem I faced was moving it. No idea about weight, but I guessed around 1,000 lbs. My neighbor was kind enough to let me rent his backhoe from him for $250. I took it down my driveway, flipped it over so I could at least wire wheel off the loose rust and prime the underside.



Next, I used the backhoe to rip out the old bridge, excavate a little dirt for new piers (plus 1 piece of 4’ rebar per block opening). I had some ¾” gravel and some rip rap left over from another on-going project.



Flipped the flatbed back over

Strapped it down and set it.


Used the hoe to turn it 90 degrees and set it into place. A backhoe makes everything so much easier.

Primed it using Sherwin Williams Kem Kromik Universal Metal Primer primer:
https://protective.sherwin-wil...25943%3Aproduct-6766

Top coated with Sherwin Williams Hydrogloss Single Component Waterbase Urethane:
http://protective.sherwin-will...26356%3Aproduct-6892


It wound up costing me a little more than what I had liked, but this bridge should out last me! Might need another coat of paint every 10 years or so, but I think that’s about it! I wouldn’t drive a car or truck across it, but it handles my ~1,300 lb tractor just fine.
Total cost was about $900
Flatbed - $500 delivered
Backhoe - $250 for the day
Primer - $53 per gallon
Topcoat - $89 per gallon

hey thats pretty cool - what a great idea - using an old flat bed

better the the Corps of Engineers (and faster )

Is there anything securing the deck to the piers?

In that second picture, I'm thinking Wile E Coyote would have dropped the bed onto the plow which would have bounced into the old Goat, and then we'd hear:

Big toys + an industrious spirit = nice job!

quote:

Originally posted by jjkroll32:
Big toys + an industrious spirit = nice job!

This. Nice work!

Nice job.

I don't know how you tied it down, but I was looking at those 2x4 loops along the long sides and thinking that'd be a good place to drive down steel posts. Maybe even wield them in place and add support for the sides.

quote:

Originally posted by BBMW:
Is there anything securing the deck to the piers?

I did think about this quite a bit. The only thing I could come up with was to use some heavy gauge, 8' green "stakes", pound them in as far as I could, then cut them off. The only problem is I was then left with something sticking up out of the ground. I have 2 boys, ages 5 & 6. And, well, boys are boys.

The more I thought about it, the biggest lateral force would be the water issue again. I would say that is a rare event, maybe once every 8 - 10 years. If my guess of 1,000 lbs is reasonable I just can't see it moving, even with water. I also raised the flatbed up about 3" over the old, wood bridge. I have since created dirt "ramps" for the transition.

I would be open to any method of securing it better if someone smarter than me gave me a method and reason. After thinking about it, I am just not sure it's necessary...but I'm no bridge builder!

quote:

Originally posted by newtoSig765:
In that second picture, I'm thinking Wile E Coyote would have dropped the bed onto the plow which would have bounced into the old Goat, and then we'd hear

quote:

I was looking at those 2x4 loops along the long sides and thinking that'd be a good place to drive down steel posts.

I was thinking they would be good for some fancy wood rails to match the little bridge in the background.

You could combine both ideas. Steel C channel driven into the ground through the stake pockets, with enough height to attach rails.

That'll be there a'while...

Nice job!

Nice job!

Nice! Would look good with some old metal manure spreader wheels for guardrails

I'd drive my truck right across that and not have a second thought.

Yep, I'd drive my pickup across it too. Not a huge unsupported span at all.

You could also bend 8'- 10' rebar into a V and pound that into the ground to affix the corners. That may be overkill though. I like overkill.