Concrete shakes loose from Oklahoma bridges

You think we would learn after the I-35, we need to repair these things, nothing lasts forever and that includes concrete

 

All the new bridges being built here now use steel beams over sections that have roads under them. Still use precast concrete beams on other sections. Too bad this lady was in the wrong place at the wrong time.

 

Concrete last's forever if it's made and laid right. It looks like to me that it was a structural problem. They probably used the wrong steal reinforcement, or spaced it out to much. Rust can cause concrete to erode and break away, as can an alkali reaction. However I think it was the contractors fault. I'd say the concrete was fine, as again to me it looks like a structural problem. SEE THE HUGE CRACK? That's cause it wasn't finished right, and I guarentee the contractor skimped on the steel.
That's the problem with bid work, not with concrete. The contractor comes down on the bid so he can get the job, but still wants to make the big bucks, so he skimps on his steel and thus you get what we saw there.
Concrete does last forever my friend, just look at some of the works of the ancients.
Oh and btw CONCRETE has been known to gain strength over a 50 year span of time. Thus concrete is like fine wine or a woman, it only get's better with age, IF it is finished correctly, and IF it isn't abused with diecing salts etc.
I love concrete.

 

you got that right!! ever tried to "ramset" a steel pin in old concrete? they just bend or concrete "blows out"

 

Its nice having a in house expert!!!!

 

There is such a thing as bad concrete, i worked for a concrete or cement plant. you use 4 to 5 bags of concrete to each yard of mix, now where i worked they were bringing in fly ash thats used to mix in with the concrete to give it strength, this place was pulling out 2 or maybe 3 bags of concrete and putting in the fly ash to skimp and make money, and they had it on paperwork in the computer as concrete not fly ash, many a pour i did from the truck turned out horribly wrong even tho it was finished right or tryed to finish it. Either it wouldnt set up or it would set up to fast then crumble, also if the sand and gravel isnt washed properly and isnt a clean mix, the cement wont set up or work properly. If you want some really hard concrete use fiber mesh in the mix, its like hitting rock when trying to break it up, works great with rebar in the form as well.

 

For a bridge deck it's going to be a 7-8 bag mix.
Fly ash doesn't gain strength UNLESS it is Class C fly Ash which is a byproduct of Western Coal. Eastern Coal contains more carbon and doesn't gain strength.
They should be turned in for skimping on the mix like that. And if they are that loose with their product I doubt they're state certified.
Fiber doesn't make concrete any stronger. Well it gains tensile strength not compressive strength. The best use for fiber is to help prevent cracking.

 

they are state ceritfied,, they are a major cement company here all now owned by oldcastle inc. but they hide it very well trust me, they have it labled in the computer system as cement powder, but i know the real truth as i used to work there and seen what the boss was doing.

 

Huh? We just call it cement. The State always checks the fly ash and Cement to make sure it meets specs. Being from the East the LOI is something you gotta watch closely. For instance I got two loads the other day, one was 1.3 the other 1.6 and the load it went ontop of was like a 0.9.

I must correct myself however. I looked at that picture again, and it was a structural problem, but I think it was just a bad subgrade. For some reason I thought it was an elevated slab when I first looked at it.
The subgrade is very important, that's why you get ruts in the road.