Re-Decking a Bridge

[wvpolekat]

I am going to be helping a friend redeck a bridge. Wish I had taken some pics, but let me describe it for now.

Current bridge is approx 20 feet long going over a small creek. Bridge is supported by 4 12" steel pipes going in the ground and then 3 12" steel pipes running the length.

Originally, the bridge had a wood deck. Sometime in the last 10 years, the previous owner put approx 3" of concrete on top of the wood deck. The concrete has wire mesh for reinforcement.

What has happened is that the wood has rotted out under the concrete and a large hole has formed, I assume because of lack of support.

The current plan is to rip up the concrete and rotten wood and redeck with new oak from a local mill.

The question is mostly regarding removing the concrete.

We have 2 kubotas to use, my B7500 and another B or BX with a hoe.

Using the current hole that is about 1 foot in diameter, is busting the concrete up with the hoe reasonable?

Renting something like a jackhammer is really not in the budget, and there is no place within an hour to do it anyhow.

 

[beenthere]

No suggestions, as the description didn't leave enough knowledge of what you are faced with to comment.
Wish you luck.

Hopefully others have a better take on the details than what was provided.

Best I could recommend would be to lift it off.

 

[wvpolekat]

No suggestions, as the description didn't leave enough knowledge of what you are faced with to comment.
Wish you luck.

Hopefully others have a better take on the details than what was provided.

Best I could recommend would be to lift it off.

Lift it off??! How do you propose we lift a 3" thick slab of concrete that is 10 feet wide and 20-30 feet long?

 

[EddieWalker]

Do you have a rotary hammer?

I've taken out pads that size behind houses that I couldn't get anything big into to haul it off, so I broke it into small pieces. My SDS Max Rotary Hammer is also a small jackhammer. It does an amazing job of breaking up concrete pads. Depending on what size the mess is, you can cut it with wire cutters, a grinder or a torch. My guess is that you can just break off the concrete from the wire and let the concrete fall into the creek bottom to act at rip rap. Might be nice for the approach to the bridge too!!!!

The hoe buckets should hanldle this easily. It's just hard to control the size of what you break off, and not damaging anything else. Until you try it, you'll never know if the results are satisfactory. If I didn't have a generator or a way to power the rotary hammer, I'd try with the bakhoe.

Have you priced what oak will cost to do the job? I would go with PT 2x8's.

My thought is the concrete held water under it, and on top of the wood. Since it would be wet for extended perioud of time, it rotted out. Once it started, the process just speeds up and gets worse.

PT wood will last decades if it's allowed to dry out.

I have oak on my land and if left out, it rots fairly quickly. I would never use it for anything exterior. I also know that there are differnt types of oak, so maybe you are buying something that I'm not familiar with.

Eddie

 

[dstig1]

Lift it off??! How do you propose we lift a 3" thick slab of concrete that is 10 feet wide and 20-30 feet long?

2 guys. Lift with your legs, not your back.:laughing:

The new decking will be White Oak, not red, I hope. WO has natural rot resistance, RO does not.

Edit: Or PT as Eddie posted (same time I was writing...)

 

[gwjd]

this adds some more work but a good coat of deck stain or selant on all 4 sides befor it is put on the brige may not be a bad idea

 

[wvpolekat]

I do believe it is white oak. It is the standard fare for bridge decking around here.

Eddie, you are correct that we can just let things fall. We can also get under there with a tractor if needed.

I am considering making up or getting something pointy to mount in my 2" receiver that is part of my plow project. Basically, it is a 2" receiver that is mounted in a 3x5 piece of steel that mounts in place of the bucket. But, I worry that would not have enough reach and would be hard on the loader.

 

[beenthere]

Lift it off??! How do you propose we lift a 3" thick slab of concrete that is 10 feet wide and 20-30 feet long?

That is as good as I could come up with, given the little bit of information provided.
Note that you didn't offer how wide the bridge was, nor whether it was a foot bridge or one to carry traffic (truck, car, tractor, lawn mowers, or whatever).

Give more information, and maybe the answers will be more in line with what you need to do. We are not the ones with the problem.

 

[wvpolekat]

That is as good as I could come up with, given the little bit of information provided.
Note that you didn't offer how wide the bridge was, nor whether it was a foot bridge or one to carry traffic (truck, car, tractor, lawn mowers, or whatever).

Give more information, and maybe the answers will be more in line with what you need to do. We are not the ones with the problem.

It's a bridge being supported with 4 12" steel pipes with 3 12" steel pipes running it's length and has a 3" concrete deck over wood. Does it sound like a foot bridge?

 

[radioman]

I really don't think you will be able to crack and pull out sections of concrete with mesh on it with an BX. The curling power is not enough. A B- maybe. It looks like you are going to be doing it with a sledge hammer and alot of elbow grease if your budget is pretty small. Once you get the pieces broken up, the BX hoe can lift the concrete sections once its loose.