03 Aug Tack Coat & Petromat Information
What is Tack Coat?
Tack coats are thin layers of asphalt product that are used in the construction or refacing of roads, highways, parking lots and even driveways. This type of product is used to help the layers of asphalt laid down as part of the resurfacing process to bond together with more efficiency. As a result, overlay is able to hold up under constant use for longer periods of time, making it easier to maintain the road properly.
Also known as bitumen, the tack coat itself is composed of asphalt by-products. The bitumen is sticky, an attribute that makes it ideal for use as an adhesive between layers of asphalt. Without the presence of the tack coat, a new layer of asphalt laid upon an existing road would deteriorate much more quickly, often creating potholes and various conditions that decrease the safety of the asphalt.
In order to achieve the highest degree of efficiency with a tack coat, it is important to prepare the section of road properly. This means that the layer of asphalt that is already present should be dry and relatively free of dirt and other contaminants. This will help to make it easier to apply a uniform layer of the product and help the tack coat provide a greater bond with the asphalt that is applied over the adhesive.
What is Petromat?
The Petromat® System extends the life of new asphalt pavements and asphalt overlays. The Petromat System consists of Propex’s Petromat non-woven polypropylene fabric which is field saturated with an asphalt cement tack coat. When placed between pavement layers, the Petromat system becomes an integral part of the roadway section, forming a barrier to water infiltration and absorbing stresses to reduce reflective and fatigue cracking of the new blacktop surface layer. Since 1965, the economical Petromat System has had an outstanding record of improving pavement performance while reducing maintenance and roadway life-cycle costs. Paving fabric systems are currently being used at a rate of over 15,000 equivalent lane miles per year in North America alone.
Stress Absorbing Interlayer
Function: Petromat paving fabric, saturated with tack coat, forms a substantial interlayer media within which stresses can be absorbed. Stresses associated with limited movement along cracks and joints in existing asphalt or Portland cement concrete (PCC) pavements are absorbed within the paving fabric system and therefore, are not translated, or reflected, up into the asphalt layer over the system. Also, asphalt concrete flexible pavement will eventually develop fatigue cracking due to tensile stresses while flexing. The inclusion of the Petromat System interlayer results in a layered pavement with greatly reduced tensile stresses compared to monolithic pavements with no interlayer. The result is a dramatic increase in the fatigue life of new pavements or overlays.