A mill and overlay is a critical part to any pavements lifecycle and comes with several benefits. Using a milling machine, 1.5 or more inches of the existing pavement surface is removed, and then the milled surface is overlaid with new asphalt pavement. A mill and overlay refreshes the pavement’s surface, but how do you know when it is time for a mill and overlay?
Signs it may be time for your parking lot to have a mill and overlay:
Minimal Fatigue Cracking
Fatigue cracking is a series of interconnected cracks typically described as resembling alligator skin. It is a structural distress, caused by overloading thin pavements or a weak aggregate base or subgrade. A mill and overlay does not address structural issues because it is only replacing the thickness of the pavement removed. Any fatigue cracking should be repaired prior to a mill and overlay.
Block cracking is the interconnection of several cracks that develop as the pavement ages. Block cracking is identified by the signature square-like pattern formed on the pavement from the cracks. When block cracking is widespread, it is an indication that the pavement is aging, and, in conjunction with minimal fatigue cracking, block cracking is a good indication that the pavement is structurally sound.
Surface deterioration, also known as raveling, is the progressive loss of asphalt material from the pavement surface. This typically occurs slowly, and over the entire surface of the pavement. It can be identified by exposed rocks on the pavement surface and the coarse appearance of the pavement. This can also be a good indicator of the age of the pavement. The more surface deterioration the older the pavement.
Pavements with drainage issues will have areas where water pools after a rainstorm. Flat areas may have multiple smaller areas with puddles of water or there may be a large area where water drains to, but does not have a catch basin for water to run into. By milling the surface at an angle, drainage issues can be improved with a mill and overlay.
If it’s still not clear whether or not your pavement is in need of a mill and overlay, contact Bituminous Roadways Inc. at 651-686-7001 to schedule a pavement assessment or complete our online Request a Consultation Form. Our professional pavement engineer will access your asphalt pavement and recommend the right maintenance technique to help maximize your pavements life cycle.