What does Norway do to prevent frost-heave on its roads?

November 30, 2005 10:41 AM

How do countries with long, cold winters deal with frost-heave in their roads? Is there a kind of frost-resistant road? Is it much more expensive?
posted by stokast to technology (11 comments total)

Frost heave is minimized by building a road base that goes deeper then the frost line. The basic thing of it then is to put in a deeper road bed.
posted by voidcontext at 10:47 AM on November 30, 2005

Also, the vast majority of damage to a road comes from the weight of traffic.
posted by voidcontext at 10:50 AM on November 30, 2005

I used to date a girl who did soil sampling for paving/construction projects with the sole purpose of delaying environmental effects as long as possible (as it is, obviously, expensive to re-pave). You're underlying soil mixture is key in dealing with a lot of weather related problems (regardless of cold/hot, wet/dry etc.) in that it can either keep moisture in or out, help with expansion and/or contraction, and simply support the amount of rock on top.

I did a Google search for frost-heave and this was the first link. Appropriately, it's from a site called pavement.com.
posted by purephase at 10:54 AM on November 30, 2005

In my travels it seems that long, cold winters aren't too hard on roads. The worst roads seem to occur in areas that have large numbers of freeze/thaw cycles, with moisture added in betwen each one.
posted by I Love Tacos at 11:02 AM on November 30, 2005

Good point I Love Tacos. I'm guess I'm thinking of places with a big temperature range between summer and winter.
posted by stokast at 11:08 AM on November 30, 2005

Ottawa, Canada has a wide temperature range. When I stepped off the plane on December 30th, it was -40C with the windchill. When I left in late August, it was +40C with the humidex. Ottawa has pioneered special sewer hole covers, follows salting guidelines, etc. Over in Quebec, they're experimenting with pavement structures.

You might have some luck Googling for frost heave and limiting the results to pages from Canada (www.google.ca). Many parts of Canada are subject to temperature extremes and frost heave has been important to our transporation infrastructure as far back as the development of the national railway in the 1800s. Also, if you Google for Canadian examples, most of them should be available in English, as opposed to docs from Norway, Russia, etc.
posted by acoutu at 11:22 AM on November 30, 2005

Russia deals with it through the time-honored method of having extremely crappy roads.
posted by agropyron at 12:20 PM on November 30, 2005

Here in Minnesota there's a stretch of I-94 that is a "research road." There are an extra two lanes going west for a stretch outside the Twin Cities that they use to test different lane striping paints, pavements, construction methods, etc. It was partially funded by the federal government. I imagine MNDOT (Minnesota Department of Transportation) would have some information for you, if you're really curious.
posted by Coffeemate at 12:25 PM on November 30, 2005

A good road base will not heave because crushed stone holds very little moisture and will drain excess moisture away from the road. Clay is notorious for causing lots of problems with heave because it holds moisture like a sponge. When it freezes, then it will expand. Irreputable contractors will save a few bucks by not putting enough aggregate in the road base. If the clay is too near the pavement then there will be problems.
posted by JJ86 at 3:09 PM on November 30, 2005

In addition to the road bed comments above, I would also add that the roads are almost always asphalt, as the asphalt is better at contracting/expanding without cracking.

Moving from northern Sweden to Atlanta was weird, as I had never seen concrete used for paving before.
posted by gemmy at 4:35 PM on November 30, 2005

Alaska deal with it by digging up enormous sections of the road system every summer and repairing it. That and
not paving them in the first place, allowign maintenance to take place witha grader. Studded tires aren't great for the road surface and supposedly are the cause of the deep grooves in many Alaskan highways. I wonder about that as many of the grooves are deeper than the asphalt is thick, I suspect it's a combination of studded tires and something else like subsidence.
posted by fshgrl at 6:43 PM on November 30, 2005