How thick should an asphalt driveway be? The answer depends on the amount of traffic and weather on the driveway. Usually, a two-inch layer of material is sufficient to withstand normal traffic. Nevertheless, for a stone surface, one inch is sufficient. This will provide a solid base for the surface and endure additional wear and tear. Here are some guidelines for determining the thickness of an asphalt driveway:
Minimum thickness of asphalt resurfacing
The minimum thickness of asphalt resurfacing is generally two inches thick. This is usually sufficient in most cases, although the thickness may vary depending on a number of factors, such as subgrade and soil compacting. In certain cases, however, more than two inches of asphalt will be required. If this is the case, the area will need to be treated with a sterilizing agent to prevent future flora growth. In addition, the subgrade should be properly graded to prevent yielding areas and pumping soil. After the initial preparation, a large truck should be driven over the area to check for weak spots and replace them with six inches of compacted crushed stone or three inches of asphalt concrete. In some cases, it may be necessary to remove the upper portion of the subgrade in order to install asphalt.
The minimum thickness of asphalt resurfacing is based on the subgrade’s strength. For example, if the subgrade is clayey, it’s recommended to install an aggregate base, or a composite base, over the top. In addition, the maximum unit weight of asphalt is 62.4 pounds per cubic foot, or 0.95 X 156.0. It’s important to remember that the minimum pavement thickness is only a recommendation and may need to be increased as required by design.
Impact of traffic on thickness of asphalt resurfacing
Several factors influence as-built pavement roughness, including the amount of surface preparation prior to overlay, the layer thickness, and the existing condition of the road before resurfacing. Some of these factors are subject to debate, and some may be overlooked. For example, roughness measurements in New Mexico and Minnesota were not available prior to resurfacing. Because of this, the study was limited to examining the effects of resurfacing on pavement roughness, with no other statistically significant interactive effects.
Results of this study demonstrate that pavements with high pavement roughness before resurfacing will have higher as-built pavement roughness. Based on the IRI before resurfacing, the regression line is estimated to be 0.29 m/km. This suggests that for every one m/km increase in pavement IRI before resurfacing, an additional 0.29 m/km will increase after resurfacing. However, the data for this regression line are limited in Manitoba and New Mexico.
Overlay thickness is associated with lower as-built roughness. The study also found a positive relationship between pavement roughness before and after resurfacing. Overlay thickness, however, had a minimal influence. In fact, the results are statistically significant. The results of this study are available in the Canadian Long-Term Pavement Performance program. To analyze the effect of these variables on pavement roughness, the researchers used a mixed-method of analysis to determine which variables contribute to pavement roughness.
Requirements for proper drainage on asphalt resurfacing
Drainage systems are essential for any paving project, and the lack of them can result in an increased number of maintenance procedures, as well as reduced material life. Water can lead to cracks in asphalt, which can cause serious accidents in the long run. Moreover, improper drainage systems can shorten the lifespan of asphalt, and reduce its overall aesthetic value. The proper drainage system will also protect the pavement from quick failure.
It’s essential that the subsurface is shaped to promote proper drainage. The new asphalt layer is one and a half to two inches above the adjacent concrete. The subgrade should be sloped to prevent water seepage or accumulation. It will also strengthen the surface beneath it. The proper drainage system will ensure that the asphalt surface will last for many years and withstand the wear and tear of resurfacing projects.
Water can cause problems for asphalt by soaking into the subsoil and causing it to crack. In addition, water can also weaken the supporting material and lead to cracks. Water damage is most likely to occur when the ground is saturated. If water cannot drain away, the asphalt will begin to deteriorate and will eventually need to be repaired. For this reason, drainage is essential for a successful paving job.