Need some engineering help

[fried1765]

I am a long ago highway design engineer (Civil).
That concrete pipe absolutely does not have enough cover material to properly distribute any meaningful load.
In addition, the 12" of concrete slab is actually a liability, as the expansion joint is above the center of the pipe adding the weight of some of the 12" slab for the pipe to also support.
The heaved slab, creating a pressure point, also contributes to the problem.
Maybe......pull a 4-5 yard dump trailer across there, towed by a pickup.
ABSOLUTELY NO TEN WHEELERS !

 

[EddieWalker]

I wouldn't risk it. There is always the chance that you will get away with it, but the odds are even better that you will damage it and then nothing will be able to go over it. What is your plan if it's damaged and nothing can get across it anymore?

Is there a way to dig out the bank of the creek and create a gravel base to drive across through the creek?

Can you remove the existing slabs and pour a solid slab over the entire pipe that is thick enough to add significant strength to it?

 

[fried1765]

I wouldn't risk it. There is always the chance that you will get away with it, but the odds are even better that you will damage it and then nothing will be able to go over it. What is your plan if it's damaged and nothing can get across it anymore?

Is there a way to dig out the bank of the creek and create a gravel base to drive across through the creek?

Can you remove the existing slabs and pour a solid slab over the entire pipe that is thick enough to add significant strength to it?

Better put some meaningful reinforcing steel (with chairs) in the bottom of that solid thicker slab too!

 

[EddieWalker]

Yes, but I'm not going to volunteer what size or spacing should be used, or how thick.

 

[crashz]

Better yet, dig it out and put a correctly sized, pre-cast box culvert in place and solve the problem of flooding too. BTW - I am a licensed Civil engineer.

You can look up reinforced concrete pipe charts and get an idea of the loading, but all depend on a certain amount of cover soil. The cover soil offers uniform loading. The slabs actually cause a point load. So even if you have a load chart, what can you reasonably expect? 1/2 load? 1/10 load? How old is it and how much corrosion and cracking has it seen? Too many questions.

 

[Jstpssng]

I just had a 12' wide bridge built with a 6 foot span for $1610 including installation. We used (2) 2x6' concrete blocks for each abutment; for decking I used skidder bridges made form hardwood. We then trucked 100K lb truckloads of wood across them. In your case you would probably go two blocks high, with some type of deadman between them, going back away from the stream.

 

[fried1765]

Yes, but I'm not going to volunteer what size or spacing should be used, or how thick.

Yep....understand/agree!

 

[4570Man]

I’d put some timbers inside the culvert to reinforce it and drive the trucks across and then drive the trucks across.

 

[fried1765]

I’d put some timbers inside the culvert to reinforce it and drive the trucks across and then drive the trucks across.

That would obviously be a one time temporary fix.
Would seem like a permanent fix (for future use) might be the better idea.

 

[4570Man]

That would obviously be a one time temporary fix.
Would seem like a permanent fix (for future use) might be the better idea.

I don’t see how you could permanently fix it without hindering the water flow or completely reworking it.