Asphalt pavement is a surfacing material made from stones, sand, and gravel, held together by asphalt cement. It is utilized in a variety of different applications because of its strength, durability, cost-effectiveness, and simplicity and speed of implementation.
Not only does an asphalt-surfaced parking lot have flexible properties, but its longevity and ease of application and repair make it a desirable construction method when it is properly laid. CI Pavement can assist you with flawless installation, overlay, and repair of asphalt. By establishing and following a plan for asphalt maintenance, you will maximize the lifespan of your property’s pavement and enjoy it for years to come.
Even the best construction materials will need occasional repair. Poor maintenance, the freeze-thaw cycle, and other extenuating circumstances can hasten the damage caused by natural aging. With asphalt, there are two basic types of repairs to consider, the suitability of each dependent on budget and the scope of failure: 1) asphalt patching and overlay, or 2) asphalt milling and replacement.
Asphalt Patching & Overlay
Asphalt overlay, also known as asphalt resurfacing, is used in less severe cases of asphalt failure or to improve aesthetics.
One of the most common forms of asphalt distress is known as raveling. Over time, water, UV rays, and gas/oil spills can erode the surface of asphalt pavement, which separates the binder from the asphalt aggregate. This, in turn, can create irregularities, cracks, and potholes on the surface.
If the underlying base is stable and still provides a firm foundation, and after inspection, the failures are deemed to be superficial and originate from the top down, an entire parking surface can be resurfaced in a process known as overlay. A hot mix asphalt is applied to resurface and renew these areas, applied at a depth of 1.5” to 2” depending on the primary use of the asphalt.
If potholes have developed, but there are no signs of base failure due to rutting, alligator cracking (interconnecting cracks that form a series of blocks resembling an alligator’s skin), sags, or lateral displacement, these may also be filled using the surface patching method.
Asphalt Overlay Resurfacing Considerations
One of the key elements to the long-term success of asphalt resurfacing is binding – how well the hot mix asphalt connects to the existing base below. Proper surface cleaning and application of a tack coat on the base layer will ensure strong binding.
To prevent pedestrian trip hazards and other liability incidents, an asphalt overlay requires a surface that is level with and provides a smooth transition to your existing curbs, gutters, approaches, ramps, dumpster pads, lot edges, and other structures. This is achieved with transitional milling, also known as wedge cutting. Not only does wedge cutting optimize your property’s appearance, but it prohibits the raveling of feathered asphalt and allows a consistent asphalt layer depth to be applied.
Asphalt Milling & Replacement
Asphalt milling and replacement is used in more severe cases
of asphalt failure when the integrity of the underlying base is compromised.
As asphalt pavement ages, fatigue cracks can develop, spread, then deepen, leading to structural deterioration. Tree roots, water leaks, and shifting soil are also common sources that can undermine the tensile strength of the asphalt. Aggravated by vehicular traffic, the compromised area allows water to wear away the asphalt binder and infiltrate the base layer, leading to pavement material erosion and subgrade failure. If this water freezes, it expands, much like an ice cube in a freezer. When it then melts, the asphalt sinks into the enlarged cavity, resulting in a pothole or sizeable cracks that will continue to expand.
At this stage, the most effective form of repair is to remo
ve and replace the deteriorated area via milling. A milling machine removes the affected asphalt and base, a cement-stabilized reconstitution of the substrate is performed, and a completely new asphalt surface is applied. This process can either simply remove and scarify the top few inches of the asphalt or it can complete a full depth repair of up to 10” below the surface, depending on the source of the issue.
Water underneath the surface of a parking lot, drive, or walkway is an asphalt adversary, shortening the lifespan of pavement. The primary access point into the asphalt and base are the unsightly and unsafe cracks that develop overtime.
Hot pour crack sealing is the first step in preventing pavement deterioration by preventing water from entering and weakening the base. It also helps preserve the pavement adjacent to the cracks from experiencing an expansion of cracking.
This process also prevents pebbles, sand and dirt from finding their way into open cracks which causing further cracking. Crack sealing is important to extending your pavement’s lifespan, and affects both appearance and safety.
We recommend giving attention to cracks early in their appearance to prevent small problems from becoming larger ones. Having crack sealing done can, in many cases, double the life of your pavement and delay the need for an entire resurfacing.
Once new asphalt is applied, it takes 90 days to cure. Proper maintenance via seal coating and crack sealing can inhibit the deterioration process by protecting the surface not only from water and weather, but also petroleum products and debris. These services are vital to protecting your investment by prolonging the life of your asphalt.