The concrete was for vertical columns. The concrete was to be 4000 psi, it was tested and none was below 3300 psi. The same are 1 footx1footx9 feet long. Four pieces of 5/8 inch rebar, he said 60 or 80. I am not a concrete man to know what that means. Said it had a ring embedded every foot. I am not too concerned about it handling my 1/2 ton pick up or 45 horsepower tractor in the short span. If I needed gravel or a concrete truck it could drive around when dry. Just curious of general strength, I can get them for between $100 to $75 depending on number purchased. He said they weigh about 1200 pounds apiece. Hope that helps some.
Concrete strength
- Thread starter yanmars
- Start date
bigdeano
Platinum Member
You could buy 1 and test it before investing in more.
downsizingnow48
Elite Member
There are online calculators the OP could use to assess the strength of those columns laid flat as beams. Dunno, maybe they would be safe, maybe not. Need to do the homework.
But only two of the nine would be working, the other seven are just sort of there. So total of 4 #5 rebars supporting the load for $700-$900. The beams have stirrups at 12" spacing which is good. Definitely safe for some loads. not sure I would put my $50k truck or $30k tractor on it.
Concrete and rebar are cheap building materials and easy to work with. If OP wants a concrete beam bridge, why not build it from scratch and make a couple proper beams with 3-8 rebars in the bottom or tension area.
But only two of the nine would be working, the other seven are just sort of there. So total of 4 #5 rebars supporting the load for $700-$900. The beams have stirrups at 12" spacing which is good. Definitely safe for some loads. not sure I would put my $50k truck or $30k tractor on it.
Concrete and rebar are cheap building materials and easy to work with. If OP wants a concrete beam bridge, why not build it from scratch and make a couple proper beams with 3-8 rebars in the bottom or tension area.
Streetcar
Veteran Member
The rebar is either 60,000 or 80,000 psi strength. 60 is most common strength
Egon
Epic Contributor
So, it still ends up being a factor in the design.
LD1
Epic Contributor
Too much guessing. Can never be 100% sure how they are made regardless of claims.
I'd but a couple, they'd make nice footings on either side. The build a proper bridge on top of that
I'd but a couple, they'd make nice footings on either side. The build a proper bridge on top of that
downsizingnow48
Elite Member
That is another question if span is 7 and length is 9 hard to make a footing in crumbley edge.
Streetcar
Veteran Member
Aggregate size is not considered in strength calculation.
Anytime you use something in a way it was not designed for you are walking new ground. Buy a culvert (metal, concrete, or plastic) and be done with it worry free.