Removal and Replacement of Existing Asphalt: Deterioration of asphalt can occur from a of lack of maintenance, overuse or simply living past its life expectancy. In such cases, old asphalt may need to be removed and replaced or refurbished with one of the following options:

• Regular Asphalt Overlay: When an asphalt pavement surface deteriorates to the point of needing repair, an asphalt overlay is an effective solution. A standard asphalt overlay consists of a new layer of asphalt applied over the existing asphalt surface. The thickness of an asphalt overlay is typically 1 1/2 inches, but type and amount of traffic as well as individual customer's needs are also considered. The existing asphalt surface may be milled if grades need to be maintained or altered. Milling is a process by which a machine is used to plane the pavement surface to an appropriate depth before it is covered with the new layer. Once the milling is finished and the asphalt overlay is completed, the customer is left with a brand new surface, ready for pavement marking.
• Complete Removal and Asphalt Replacement: Severe subgrade deficiencies may require complete removal of part or all of the asphalt and base material. After excavation and removal, pre-existing conditions in the subgrade such as excess moisture, shallow utility lines, missing aggregate base, or incorrectly prepared subgrade may require additional steps in the base preparation. These conditions are usually not discovered until the overlying asphalt is removed. After careful inspection, we can recommend the most effective methods to resolve these conditions. When pre-existing conditions have been corrected, new aggregate is supplied as needed and re-compacted. The new asphalt is then placed and compacted with vibratory rollers to finish the repair.

Causes of Asphalt Surface Deterioration: The most common causes of asphalt deterioration are water accumulation in areas of lower elevation, excessive loads on the asphalt, and the destructive effects of vehicle oil and gasoline. Over time, water accumulation can cause asphalt to crack and split severely, or "alligator" as it is commonly referred to in the paving industry. Bearing excessive weight can cause the asphalt to sink, and oil and gasoline that seep into the asphalt cause further deterioration.

Asphalt Patching Methods: When areas of asphalt deteriorate and need to be repaired, Paving Contractors San Antonio TX can correct the problem by using one of two methods:

• Skin Patching is recommended when the underlying base is structurally sound and is typically used on depressed surfaces. This process is accomplished by cleaning the existing pavement, applying a tack coat (asphalt-based glue), and applying hot-mixed asphalt. The new asphalt is then mechanically compacted. Because the skin patches are placed on top of existing pavement, the finished surface may be slightly higher. The edges are blended in, or "feathered," as much as possible.
• Asphalt Removal and Replacement, or R&R, is used for more severe deterioration, especially when the underlying base has been affected. The damaged areas are squared off, saw cut, and excavated to a depth from two inches to two feet depending on the subsurface conditions. New aggregate is then added, if required, and compacted in preparation for the new asphalt surface. Finally, hot-mixed asphalt is placed over this layer and compacted. Any raveled surfaces (surfaces in which the aggregate is coming loose) are then smoothed out and re-striping can be done, if needed. Paving Contractors San Antonio TX also recommends treating the entire surface with a seal coat to restore the original look of the area and further protect it.

Benefits of Asphalt Patching: Both Skin Patching and Removal and Replacement are economical components of an overall pavement maintenance program. One benefit of timely asphalt patching is the prevention of more expensive repairs in the future. Also, creating a safer environment results in fewer accidents and, ultimately, reduced ownership liability.