Hot asphalt is more finicky than most people realize: It can’t fix pavement in cold and wet conditions. That’s why newer asphalt formulations were devised.
It’s remarkable that asphalt has and continues to be so important in modern society. For all our technologies in a digital age, having flat pavement for cars, trucks, buses and bicycles is as important as ever. When potholes and lengthy road building activity slow traffic, it reduces the speed of commerce and takes time away from peoples’ lives.
So how can America maintain its $2 trillion-plus investment in its streets, roads, and highways? The smartest way is through regular maintenance.
This is why it’s good news that technology hasn’t overlooked asphalt. To the untrained eye it all looks the same, but the aggregation of small stones with black gooey stuff comes in different types made for different situations.
A good example of this is EZ Street cold asphalt. Made of a proprietary polymer-modified mix, it is formulated specifically for pothole repairs. Two characteristics make this specialized asphalt the smart product for fixing existing pavement:
Cold application: Regular asphalt, both what’s used for original road building and often for road repairs, has to be transported and used while hot and while the surrounding pavement is above certain temperatures as well. It leaves the manufacturing plant at 270 to 325 degrees F and needs to be kept close to those temperatures in transport. If the ground temperature is below 50 degrees F, the new asphalt cools too fast which adversely affects the required compacted density. This is why hot asphalt plants aren’t even in operation during the winter months in northern latitudes.
Those required conditions of traditional hot-mix asphalt make it virtually impossible to repair pavement in winter conditions – which happens to be the time when potholes form due to excessive moisture and freeze-thaw cycles. So what is traditionally used is temporary (i.e., lower quality) “throw and go” loose asphalt to fill the potholes. It performs poorly and needs replacement in spring and summer months with a more permanent fix. Labor costs are effectively doubled because those potholes have to be fixed twice.
The polymer-modified mix from EZ Street eliminates the need for that second step, providing a better, permanent fix on a single application.
Wet conditions application: The presence of water and ice can lessen the bond between new asphalt and the surface area to which it is applied. This clearly hinders pothole repairs in the presence of snow, ice and rain, and each of those things is problematic when you are trying to keep the asphalt hot (as described above). Even in summer temperatures, a heavy rain can halt paving and pavement repair activity with traditional hot-mix asphalt.
Changing the game is EZ Street premium cold-mix asphalt and its green alternative, Bioblends, which is made with recycled non-fossil fuel materials. Both can be applied in standing water – the kind that can mask potholes and cause significant damage to vehicle undercarriages – and still form a permanent bond with the surrounding pavement.
The product is formulated according to the available aggregate used by local paving firms. A little known fact of crushed granite is that subtle differences in porosity and moisture content can affect performance. The EZ Street laboratories analyze samples to adjust the emulsifier formulation, which optimizes its performance and application efficiencies.
In other words, rainy days and cold seasons don’t get in the way of repairing a busy street or highway. It is used as a pavement fixer for overlays and edge repairs, utility cuts, trench patching, and drain surrounds by contractors and departments of transportation (DOTs). Road maintenance crews keep a small quantity on board their vehicles for the occasional pothole found while doing other work. Tamping can is done with shovels or simply by driving a vehicle over the repaired surface.
A final note: Pavement maintenance is very often a means of saving taxpayer money over time. According to TRIP, a non-profit national transportation research group, “The timing of the maintenance and rehabilitation of road surfaces is critical, impacting the cost-effectiveness of the repairs and ultimately the overall quality of a regional road network…a pavement preservation program can reduce the life cycle costs of a pavement surface by about one-third over a 25-year period.”