Article: Sustainable Options in Pavement Maintenance
Sustainability is the capacity to endure. In today’s world, it is of the utmost importance to respect our resources and conserve what we can. In the asphalt paving industry, it is now easier than ever to do just that, as recycling and responsible alternatives exist which can aid in the significant reduction of energy, waste, and pollution. These sustainable options may also qualify for various LEED® credits.
One sustainable pavement improvement option is full depth recycling or full depth reclamation (FDR). FDR is a maintenance process which reconstructs existing deteriorated asphalt pavements through a recycling process. A reclaiming machine is utilized to uniformly pulverize and mix the existing asphalt, base and sub-base materials, leaving them in place for enhanced restructuring. During the pulverizing process, water and a variety of materials, such as fly ash, dry cement, asphalt emulsion, or lime can be incorporated for the achievement of proper moisture content and additional structural integrity. Once properly graded, the new base can then be compacted to produce a structurally sound and durable base for a new pavement surface.
Since FDR is an in situ process, import and export trucking of material is reduced by a ratio in the range of 40 to one, and in comparison to new full depth reconstruction, FDR reduces overall upfront costs by 30% – 50%, all while providing dramatic lifecycle savings through the reduction of future maintenance costs. Furthermore, carbon emissions and community disturbance is significantly reduced and natural resources are preserved by using existing materials and conserving virgin aggregates.
Similar to FDR, asphalt pulverization allows for the reuse of the existing asphalt layers in lieu of disposal, again through the utilization of a reclaiming machine to pulverize and blend the existing deteriorated asphalt into a new, homogenous mixture which can be compacted in place as sub-base material.
The utilization of “high RAP”, as a constituent within hot mix asphalt (HMA), and going beyond the typical 10% – 30% by weight range, has a great economical and environmental impact in pavement recycling. High RAP as high as 80% – 100% by weight has been proven feasible. In addition, new “high RAP” pavement can be created through the induction of bio-based restoration agents, without heating or the utilization of additional oil, cutback, or polymers.
Let’s not forget other recycled options for pavement facilities such as the use of rubber bumper blocks. Made from 100% recycled rubber, these parking blocks will not warp, chip, crack, or rot, effectively eliminating the need for maintenance. They install with ease and are highly visible at night, reducing the risk of damage to vehicles or personal injury.
Ultimately, by utilizing paving practices and materials that conserve resources, facilities can help ensure future growth and development in a cleaner, healthier environment.
This excerpt is from an article written by Larry Briar, Business Development Executive for Rose Paving Company. First published in Northern IL Real Estate Magazine in August 2011.