The steps to a durable solution
By Jeff Winke
Given the options, it is becoming clear that infrared repair may be the best choice for performing critical asphalt pavement repairs that do not need more extensive resurfacing or replacement. It is the process through which existing, damaged pavement is heated and replenished before being mixed with new asphalt and compacted.
An infrared heating unit heats in-place asphalt to soften it to a workable state. New asphalt can be added if needed to fuse seamlessly to the old. Compared to the old saw-cut method, where a square of damaged asphalt is cut out, removed and filled with new hot mix asphalt, the infrared method eliminates the seams that can ruin the effectiveness of saw-cut patches. The infrared advantage is the feathered joining of the new patch material to the surrounding pavement. Being seamless can eliminate water infiltration. Saw-cut seams permit rainfall to enter, which can introduce moisture and freeze/thaw damage into the patch, which means many such patches will have to be redone yearly or sooner.
What is the process in order to make sure your infrared repair lasts? There are numerous information articles and how-to videos available. Ray-Tech Infrared, KM International and ARS, LLC all have several instructional videos that address how best to use infrared asphalt recyclers for repairing compromised pavement.
Step One: Clean the repair area —The area to be treated is swept or blown clear from debris and thoroughly dried out to ensure that nothing blocks the infrared repair unit from reaching the asphalt surface.
Step Two: Unload the unit from the transport truck and prepare it for use —Make sure to inspect it for any damage or obstructions and then position the wheel casters for use.
Step Three: Position it over the damaged area —The infrared heater is placed above the damaged asphalt area and make sure to position the wind skirts to keep the machine stable.
Step Four: Heat the damaged paved area for about 5-10 minutes —This heating time may vary depending on the existing aggregate, the season, and the depth of the damage. More extensive asphalt pavement damage takes longer to treat.
Step Five: Scarify and rake treated area —Rake to remove loose and failed aggregate. Scarify the surface.
Step Six: Add rejuvenator —A rejuvenator should be added to the remaining aggregate, replenishing oils lost through age and oxidization.
Step Seven: Add or remove materials as needed —New asphalt can be added and mixed in, ensuring the asphalt is then graded to the proper level.
Step Eight: Lute the repair area —Luting freshly placed hot mix asphalt will make a difference. Luting is like raking, but where raking is moving mounds of material, luting is the “fine tuning” of the asphalt mat. It involves taking off the stone and manipulating the mat to eliminate imperfections.
Step Nine: Compact the repair area —Once the repair area’s new hot mix asphalt is added and thoroughly mixed, the area is compacted with a multi-ton vibratory roller or plate, to create a seamless patch. Compact the edge area first is best.
Step Ten: Clean the repair area after complete —Open to straight drive over traffic when the finished cleaning is completed, but wait 45- to 60-minutes for turning traffic.
Due to the heat penetration of infrared rays, asphalt can be repaired and reclaimed without risk of burning, scaling, or separating the asphalt from the aggregate itself. Mixing the existing asphalt with new material results in a seamless repair, which prevents moisture damage by eliminating the possibility of joints which can allow water to seep into the repair.
With fewer raw materials needed, this method of asphalt repair is more cost-effective. Infrared repair is also a more time-effective process than other repairs, since it takes less time to patch and the resulting repair can be driven on almost immediately.
As stated by Bob Kieswetter, president of Heat Design Equipment Inc., Kitchener, Ontario, Canada, “The key features of infrared include that the process leaves sealed watertight joints for longer durability of the patch, requires less equipment on site, and it is a quieter and less intrusive repair process.”
To conclude–especially with this time of year in mind–a big benefit of infrared asphalt pavement repair is that it can be performed any time of the year-–from the heat and humidity of the summer sun to freezing, snowy cold in winter. This method of asphalt repair is always viable. The treatment can be used when it is too cold for hot mix alone, which also boosts its cost-effectiveness since asphalt repair costs often rise in the winter due to the increased amount of machinery needed to keep materials at the correct temperature. Infrared asphalt repair can eliminate these additional costs.
No matter when a repair is needed, the steps to a durable long-lasting pavement repair can be taken.
Jeff Winke is a business and construction writer based in Milwaukee, Wisconsin. He can be reached through jeff_winke@yahoo.com