Diane Hammonds, the Branch Manager for Sain’s Louisiana [...]
By: Matt Stoops
We’ve all seen paving crews out working at some time or another. But what are they doing – especially when the road seemed to be in fine shape? Well hopefully the city, county, or state is being proactive about doing preventative maintenance. The buzz word on this right now is called Pavement Preservation. It is way more cost effective to do preventative maintenance rather than let an asset deteriorate where it needs total replacement. If you had a leak in your roof, would you just ignore it and wait until it was time to replace the entire roof? No, because the leak would cause other damage and by fixing the small damage, you can add years of life to the rest of the roof. The same principle applies with pavement, and it is usually a water leak that causes the damage. Sealing a road to prevent water intrusion helps preserve the life of a pavement.
There are many methods for sealing a road depending on its current condition. Sain has been working to advise cities of some of the lesser used alternates. The most typical maintenance is the 2-inch overlay of additional asphalt hot mix paving. But this is one of the more expensive options at around $13 per square yard. This puts out a new surface that is sealed, and also adds some structural strength. This overlay is best for a road that has significant cracking and rutting problems.
If a road has moderate cracking and very minor rutting, Microsurfacing is a good option at a cost of around $4 per square yard. This method places a slurry of asphalt with a small portion of sand and fine gravel to add about ¼” of thickness to the pavement. This thin layer, it does not add any significant strength to the pavement, but it does fully seal the road, and can correct very small rutting issues.
If cracking is the only problem, but the cracks are across the full roadway width, then there are several types of sealing applications that spray liquid asphalt across the full road. The asphalt works its way down into existing cracks and prevents further water intrusion. These typically cost around $2-$4 per square yard.
Lastly if there are mostly linear cracks, then manual crack sealing is a good approach. In this method a laborer manually works sealant into a crack, usually via a wand and hose attached to a trailer. Crack sealing is very inexpensive at around $0.10 per square yard.
Similar to home maintenance, Pavement Preservation encourages preventative maintenance in order to avoid further, more costly repairs down the road.