Has anybody seen these on expressways?

[gindie]

There was some rehab done recently to some all-concrete expressways in our town and when they were finished, the road had the little 3-block areas embedded in the lanes, as represented in the picture I have attached. I have since noticed them on several other stretches of interstates in other states on construction that appears to be relatively new.

I don't know if they are some sort of pavement expansion areas, or abrasions, or what, as I am usually driving 70 mph over them.

Does anybody have an idea?

 

[Ed_The_Gypsy]

I have seen them, too, and wondered the same thing.

 

[omni550]

What city were these in?

 

[gindie]

Nothing like answering one's own question. I don't know how long I have searched on Google for the answer, but didn't put in the right words.

The "bars" are created during a pavement rehab process called Dowel Bar Retrofit. Learn something new every day.

Dowel bar retrofit - Wikipedia, the free encyclopedia

 

[gindie]

What city were these in?

I live near Dayton, OH and saw them on US 35, west of I-75.

I have also seen them in Michigan on I-75 south of Detroit and in Indiana on I-469 around Fort Wayne.

 

[MooreBonds]

About how far apart are they (going from North to South)? I've seen somewhat 'similar' markings, which (AFAIK) are used by patrol vehicles (airplanes or patrol cars) for timing cars passing over each pair to estimate speed and handing out tickets.

Are they painted on, or are they grooves in the road that are concrete/pavement, and not readily distinguishable from the rest of the road from a distance?

 

[omni550]

Also, by your rough approximation, how wide was each individual depression and how long was the overall "patch" of depressions?

 

[omni550]

Nothing like answering one's own question. I don't know how long I have searched on Google for the answer, but didn't put in the right words.

The "bars" are created during a pavement rehab process called Dowel Bar Retrofit. Learn something new every day.

Dowel bar retrofit - Wikipedia, the free encyclopedia

Interesting. Thanks. Now that you mention it, I do recall seeing the ones south of Detroit.

Hope the retrofit solves the problem.

omni

 

[gindie]

About how far apart are they (going from North to South)? I've seen somewhat 'similar' markings, which (AFAIK) are used by patrol vehicles (airplanes or patrol cars) for timing cars passing over each pair to estimate speed and handing out tickets.

Are they painted on, or are they grooves in the road that are concrete/pavement, and not readily distinguishable from the rest of the road from a distance?

According to the Wiki page I finally found, they are placed across cracks in the pavement. They are filled-in slots that have been cut into the pavement. The color of the fill is not exactly the same as the pavement, so they are distinguishable. They are always in 2 groupings of 3 across the lane, placed where the wheels normally travel.

According to the Wiki page, once they are done with the cut and fill operation, they basically "sand" down the entire pavement, so that the filled areas are flush with the rest of the pavement.

I can attest that once the operation is completed, the road is a smooth as silk.

 

[frayne]

They are kind of like crop circles, no ones knows where they come from !

 

[Walt34]

Aw, I was hoping they were binary codes for autonomous cars.

 

[clifp]

Aw, I was hoping they were binary codes for autonomous cars.

I think that is what they basically are. Skylab is doing prep work for the eventually take over by the machines..

 

[mickeyd]

I think that is what they basically are. Skylab is doing prep work for the eventually take over by the machines..

I was thinking "BAR CODE" until the true answer appeared.

 

[lemming]

So what happens when the concrete crumbles and you have the end of a dowel just slightly above the drive surface. Looks like Tire Eaters to me.

 

[aja8888]

They are like cross-hairs for the android coming...

 

[Koolau]

I often drive a stretch that looks like the pattern shown. I can't be certain what your highway strips are, but here in Paradise, we have a stretch of "Interstate" which used to be incredibly "wash-boardy". The ground under the stretch had sunk in several spots. Although the pavement looked fine, at about 55 to 60, one felt as if there were a small earthquake going on while driving the stretch. The engineers closed small sections (and lanes) of the highway, one at a time. They pumped in concrete with a boom. Once everything was sealed, they sanded off the highway so that it was smooth over the entry points. The wash-board effect was completely gone. Apparently, they actually "pumped up" the highway to make it even. SWAG is that is what you are seeing. YMMV