Transportation infrastructure investments make a major part of National Gross Domestic Product. Each year the hot-mix asphalt (HMA) is a vital part of this investment. Hot-mix asphalt is the predominant material in pavement construction, reconstruction, maintenance and rehabilitation projects. Today, many roads and highways have exceeded their design lives and will require reconstruction, rehabilitation, and maintenance in order to continue serving the needs of our economy and traveling public. The asphalt related organizations, including government agencies, industry, contractors and research centers, understands the importance of HMA on the nation’s transportation system. Because of this enormous impact on the economy, there is a continuous effort to improve the quality and performance of asphalt pavements, including the production and placement of HMA materials and research to discover new innovations to enhance asphalt pavement-related products. Public agencies and the private sector are using the services of asphalt industry products.
Estimated price associated with pavement construction and reconstruction in past few years were grown up, for this reason recycling of asphalt pavement has proved to be a cost effective method of pavement rehabilitation and recycling operations are started as a method of reusing waste materials. Recycled asphalt production has been used and exploited as one of the asphalt mixtures for the last 40 years. Asphalt RAP (Recycled Asphalt Pavement) components are made of valuable materials. These components can be used along with new stone and bitumen materials to produce a quality asphalt mix. The economic and environmental benefits of using RAP are undeniable, and it has attracted the attention of managers of road and asphalt industry. Evidence of this claim is the growing trend of using recycled asphalt in developed countries in recent years.
Recycled asphalt production has been used and exploited as one of the asphalt mixtures for the last 40 years. Asphalt RAP (Recycled Asphalt Pavement) components are made of valuable materials. These components can be used along with new stone and bitumen materials to produce a quality asphalt mix. The economic and environmental benefits of using RAP are undeniable, and then it has attracted the attention of managers of road and asphalt industry. Evidence of this claim is the growing trend of using recycled asphalt in developed countries in recent years.
Economic and cost analysis of using RAP could be calculated in different ways. The cost associated with recycling can be presented on a material cost as well as construction cost basis. As a simple example of cost analysis; a materials analysis is presented here. This example shows the amount of savings that can be made by using recycled asphalt pavement (RAP) instead of using virgin material.
|
HMA Used Material (Percentage) |
|
| Material | Used Material Percentage |
| Virgin Aggregate | 94% |
| Virgin Bitumen | 6% |
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HMA Material Usage Comparison of 50% RAP (Percentage) |
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| Material | HMA Material (Percentage) | Recycle Asphalt (50% RAP) | Material Saving
(Percentage) |
| Virgin Aggregate | 94% | 47% | 50% |
| Virgin Bitumen | 6% | 3% | 50% |
Materials savings will depend on…
- Virgin bitumen cost
- Bitumen content of the mix design
- Aggregate cost
- Bitumen content of the RAP
- Percentage of RAP
- Market situation
Now for any specific projects with its own specification the cost saving on the base of percentage of RAP, virgin bitumen, virgin aggregate, rejuvenator and bitumen additives could be done.
