Asphalt is the smooth, quiet, durable and sustainable surfacing material that has been around for hundreds of years. Today's asphalt is a scientifically designed product. It is rut, shoveing and crack resistant. It is the most reycled material in the world.
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Check the compacted patch for a slight crown. If a depression is present add more patching material and compact.
Although it may seem that the semi-permanent technique would produce a higher quality patch than the throw-and-roll technique, the FHWA's Long Term Pavement Performance (LTPP) Study found that the "throw-and-roll technique proved just as effective as the semi-permanent procedure for those materials for which the two procedures were compared directly" (FHWA, 1998). Since the semi-permanent technique is more labor and material intensive, the throw-and-roll technique will generally prove more cost effective if quality materials are used.
KAPA Pavement Note on Throw-and-Roll
Maintenance forces in some jurisdictions use “High Performance Premix” patching mixtures and the throw-and-roll technique for pot hole patching, especially in cold weather. Materials that meet the High Performance Premix spec used by the Purchasing Office have been found to work well even when no debris or water removal preparation is performed on the pot holes. When pot hole patching is specified in a contract, however, the use of HMA and complete pot hole preparation is normally required, as well as thorough compaction. Injection type patching requiring special equipment to mix the aggregate and bituminous material on site and spray the mixture into a pot hole is also used where a large number of pot holes must be patched.
Rehabilitation/Maintenance
The Asphalt Story
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