e the newly constructed surface may be reopened to traffic in approximately 30 minutes. Because of these factors, micro-surfacing is frequently regarded as the most efficient and cost-effective form of road repair by microsurfacing providers.
The standard micro-surfacing procedure
- Visual examination of the road section to be maintained and repaired to ensure that it is suitable for micro-surfacing treatment and that no preparatory work is required.
- Cleaning the road surface properly with a road sweeper and/or a high-pressure water cleaner.
- All road furniture, such as manhole covers and gullies, must be marked and taped.
- Installation of the first micro-surfacing layer: A maximum aggregate size of 8mm is used to re-profile the road surface. If the existing road surface shows signs of a lack of bitumen content, an additional tack coating of bitumen emulsion is strongly recommended as a bonding agent. Spraying and applying the first layer of micro-surfacing in one pass is possible with a machine equipped with an integrated spraybar.
- The second micro-surfacing layer can be applied 45 minutes after the re-profiling layer has been applied. Its aggregate size is limited to 5mm. It is critical to apply this homogeneous micro-surfacing mix correctly. A variable-width distributor box with augers can be used to achieve a good surface finish.
Guidelines to micro surfacing by contractors:
Micro-surfacing should be used instead of conventional seal coats at the following locations:
- approaches to major intersections,
- urban arterials with an asphalt surface,
- interstate pavements with an asphalt surface,
- other high traffic asphalt surface pavements, or
- when traffic volume is too high or vehicles perform too many turning and stopping movements for a conventional seal coat.
Micro-surfacing asphalt is appropriate for road surface rehabilitation under all load classes of running traffic. Practical experience by microsurfacing contractors has demonstrated that micro-surfacing may endure between 7 to 8 years, demonstrating the outstanding performance and effectiveness of this modern road maintenance technique.