95.3 / 88.5 FM Grand Rapids and 95.3 FM Muskegon
Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

M-6 in need of fix MDOT seeks expert opinions for improving concrete

commons.wikimedia.org
/
commons.wikimedia.org

In 2004 the Michigan Department of Transportation spent $370 million constructing the South Beltline. Three years from now MDOT will resurface two, three mile sections of M-6 where seams are prematurely deteriorating. The warranty on the surface expired before it failed.

Why are portions of M-6 crumbling now and what is the state doing about it?

“You know, nobody is happy about this and the fact that M-6 has shown this rapid deterioration.” Jeff Cranson is Director of Communication with the Michigan Department of Transportation. “The section that’s showing this premature deterioration is about 12 years old and that’s consistent with some other states and that’s why we brought Dr. Taylor here from Iowa State University who really is a national expert and he’s done a pooled study looking at this problem.”

“The extent of the problem is limit in that not every road is doomed to die,” says Peter Taylor, director of the National Concrete Pavement Technology Center. Dr. Taylor explains concrete highway surfaces should last 20 to 40 years.

“However, there are a few, like M-6, which are failing at the joints a lot earlier than we would like. It starts off with shadowing. The saw cut across the width of the concrete starts to get a little darker and then it starts to crack and fall off. The agency usually goes back in and does some sort of patch and now you’ve got speed bumps every 14 feet.” 

What is the typical cause for that to happen?

“Two fundamental mechanisms are happening. One is freezing and thawing of saturated concrete. Concrete is a bit like a sponge. And if water gets into that sponge, freezes it expands, and causes cracking. We normally provide little air bubbles in the concrete for that expansion to go into. If those air bubbles are compromised they stop working. That can be one of the causes. The other one probably more significantly, some of the de-icing salts that we’re using at present, the more modern materials like calcium chloride, magnesium chloride, goes through a chemical reaction that causes the paste, that’s the glue, to expand and crack and fall apart.”

Dr. Taylor’s study paid for by eight states, including Michigan, and the federal highway administration recommends improved drainage, the air bubble mix, and increasing the amount of paste to combat aggressive de-icers.

Should MDOT decide to make repairs to M-6 using concrete, new specs will be implemented. However, it will also depend on contractor bidding the M-6 job.

Patrick Center, WGVU News.

Patrick joined WGVU Public Media in December, 2008 after eight years of investigative reporting at Grand Rapids' WOOD-TV8 and three years at WYTV News Channel 33 in Youngstown, Ohio. As News and Public Affairs Director, Patrick manages our daily radio news operation and public interest television programming. An award-winning reporter, Patrick has won multiple Michigan Associated Press Best Reporter/Anchor awards and is a three-time Academy of Television Arts & Sciences EMMY Award winner with 14 nominations.