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Inside the Wayne County lab that tests concrete used to fix roads

Posted at 5:24 AM, Apr 20, 2022
and last updated 2022-04-20 07:03:43-04

(WXYZ) — This year's pothole season has been brutal, but a group of engineers in metro Detroit are working to make sure the roads of the future can withstand all types of conditions.

I paid a visit to the Wayne County Department of Public Services Lab to see what they're working on.

Right before the pandemic, we checked it out, and we wanted to see what was new.

Special lab test what makes up our roads

“People are going to be asking, 'why do you guys have this testing lab if we still have potholes all over the place?' So back in the day, what happened was the mixture that we used to use, there used to be a lot of alkali-silica reaction," Animesh Aggarwal, the deputy director of the Department of Public Service, said.

Basically, what was used back in the day was a bad concrete mixture. They don't use that material anymore, and they have a more suitable material so they don't see as strong of reactions.

The lab works to make sure the material that is used now is up to standards.

A concrete mixture of rock and other material is broken, done and tested. it's the same with asphalt.

“We approve the contractors' mix design, they submit it, we say OK, and we check it," Erika Cox, the testing lab inspector, said.

“We want to make enough room freeze thaws to be able to take place, so when it gets cold the water expands and it needs rooms to leave to move," she added

In one test, we saw how much pressure a concrete mixture can withstand. Concrete is mixed and a sample cylinder is taken, put into a room, filled with moisture and allowed time to strengthen.

“That is our goal, to make it strong enough in 28 days or sooner than that," Aggarwal said.

The piece of concrete sits for six days, and then the crack is analyzed.

“So looking at the stuff that Erika broke, depending upon the kind of angel that we see, it seems that it types one break which says ‘reasonably well-formed cones on both ends," they said.

In a perfect world, we could take all the concrete that is tested, found to be good, and put it out on the roads to fix them.

However, concrete is expensive, so while we are able to test to make sure it's good, fixing our roads is going to take time and money.