<p><p><figure id='attachment_2529' style='max-width:600px' class='caption aligncenter'><img class="wp-image-2529" style=“border: 1px solid black;" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Photograph of a RMI Resonant Breaker used to break up concrete pavements." width="600" height="363" /><figcaption class='caption-text'> Rubblization using RMI Resonant Breaker (Photograph courtesy of Resonant Machines, Inc. 2005)</figcaption></figure><h2>Basic Function:</h2>Beneficial reuse of material uses wastes and byproducts in transportation applications.<br><h2>Advantages:<em> </em></h2><ul> <li>Environmental benefits in minimizing landfill space</li> <li>Reduced cost of roadway maintenance and construction</li> <li>Speed of installation</li> <li>Pozzolanic-stabilized mixtures provide a strong durable mixture</li> <li>Blast furnace slag has insulating value</li></ul><h2>General Description:</h2>Beneficial reuse of waste materials is using waste and byproducts in pavement materials, base courses, subbases, or subgrades. Wastes can be incorporated into asphalt concrete pavements, Portland cement concrete pavements, granular base embankments or fills, stabilized bases and subgrades, and flowable fills.<br><h2>Geologic Applicability:</h2><ul> <li>Untreated gravel, sand and gravel, pea gravel used in edge drains, clayey-sand, clayey-gravel, and waste foundry sand as a fine aggregate.</li> <li>Shredded waste tires (WT) fill can be blended with sand or other granular soils up to 40% by volume of the embankment fill portion.</li> <li>An assessment should be made in sites with sandy soils, shallow ground water or close to drinking water aquifers.</li> <li>Embankment construction soils range from granular soils which are highly desirable to fine grains soils (silt and clay) which are less desirable.</li></ul><h2>Construction Methods:</h2>Waste and byproducts used in transportation applications includes baghouse fines, blast furnace slag, coal bottom ash/boiler slag, coal fly ash, FGD scrubber material, foundry sand, kiln dusts, mineral processing wastes, MSW combustor ash, nonferrous slags, quarry byproducts, reclaimed asphalt pavement, reclaimed concrete material, roofing shingle scrap, scrap tires, sewage sludge ash, steel slag, and waste glass. These wastes are incorporated into projects such as asphalt concrete pavements, Portland cement concrete pavements, granular base embankments or fills, stabilized bases and subgrades, and flowable fills.<br><h2>Additional Information:</h2>Studies have been conducted on using waste materials and byproducts. FHWA encourages the use of these secondary materials in construction and rehabilitation of highway infrastructure. Some recycled material can help insulate against frost. Fly ash can be cost effective in hot mix asphalt paving applications.<br><h2>SHRP2 Applications:</h2><ul> <li>Embankment and roadway construction over unstable soils</li> <li>Roadway and embankment widening</li> <li>Stabilization of pavement working platforms</li></ul><h2>Example Successful Applications:</h2><ul> <li>Flowable fly ash grout mix, McGee Creek Aqueduct Project, OK</li> <li>State Route 22 Project, GA</li> <li>Route 213/301 Overpass Project, MD</li></ul><h2>Complementary Technologies:</h2>Chemical stabilization, hot &amp; cold recycling, full depth reclamation, grouts for pavement subsealing<br><h2>Alternate Technologies:</h2>Traditional use of virgin materials in bases, subbases, subgrades and embankments.<br><h2>Potential Disadvantages:</h2><ul> <li>Transportation costs</li> <li>Lack of regulatory and agency support</li> <li>Lack of specifications and design standards</li> <li>Leaching of elements into the ground</li> <li>Dust control measures may be needed.</li></ul><h2><strong>Key References for this technology:</strong></h2>EPA-ACAA (2005). Using coal ash in highway construction: A guide to benefits and impacts, Rep. no. EPA-530-K-05-002.</p><p>Hicks, R.G., J.R. Lundy, R.B. Leahy, D. Hanson, and J. Epps (1995). Crumb Rubber Modifiers (CRM) In Asphalt Pavements: Summary of Practices in Arizona, California, and Florida, Report No. FHWA-SA-95-056.</p><p>Sullivan, J. (1996). Pavement Recycling, Executive Summary and Report. FHWA-SA- 95-060.</p></p>