WATER: It is commonly known that water is a major enemy to asphalt. What is often not noticed is how much over-watering there is on most parking lots with landscaping. This over-watering is extremely detrimental to the life span of asphalt. The constant overflow of water actually erodes the fines, or binder, that holds the aggregate together. This can be seen on any parking area where the water flows. Just look at the difference between the smooth surface where water does not run, compared to the rough surface where the flow is. Water also enters all the small cracks and the degradation is intensified as described above. Another factor with water is the hydraulic forces acting on the asphalt surface as vehicle tires compress the water into tiny crevices and cracks, once again, eroding the pavement. Over-watering leads to the greatest cause of pavement failure within parking areas.
OIL, GREASE, AND GASOLINE: Additional factors damaging to asphalt include oil, grease, and gasoline. This is evident at any parking area within any single parking stall. Just look at where the vehicle’s engine would be if the vehicle was parked and notice the oil saturation. This saturation over a short time actually penetrates the entire thickness of the asphalt in that area and weakens it. Pressure washing and burning the asphalt will help with removing the surface oils and grease but again, the asphalt is usually saturated beyond the surface. This area will erode continuously until replacement is the only option.
CHEMICAL OXIDATION: Chemical oxidation is intensified by the suns ultraviolet rays. When new, asphalt is resilient to constant flexing but as it hardens it becomes brittle and more susceptible to cracking. Additionally, the older asphalt becomes, the more susceptible it is to vehicle wear and tear.