Roller-compacted concrete, or RCC, takes its name from the construction method used to build it. We place it with high-density asphalt paving equipment,then compact it with rollers. RCC has the same basic ingredient as conventional concrete: cement, water, and aggregates. But unlike conventional concrete, it's a drier mix—stiff enough to be compacted by vibratory rollers. Based on the client's needs, RCC may be constructed with or without joints. It needs neither forms nor finishing, nor does it contain dowels or steel reinforcing. These characteristics make RCC simple, fast, and economical.
RCC got its start in the Seventies, when the Canadian logging industry switched to environmentally cleaner, land-based log-sorting methods. The industry needed a strong pavement to stand up to massive loads and specialized equipment. Yet economy was equally important: log-sorting yards can span 40 acres (16 hectares) or more. RCC met this challenge and has since expanded to other heavy-duty applications.
Roots in Logging
Durability—even under severe loads— gave RCC pavements their start for log-sorting yards. |
Today, RCC is used when strength, durability, and economy are primary needs: Port, intermodal, and military facilities; parking, storage, and staging areas; streets, intersections, and low-speed roads. The reason is simple. RCC has the strength and performance of conventional concrete with the economy and simplicity of asphalt. Coupled with long service life and minimal required maintenance, it is highly like that utilizing RCC can save significant money without compromising quality. RCC's economy of scale made it ideal for roads, parking, and staging areas at the HONDA PLANT in Lincoln Alabama. At over 1M square yards, it's the largest RCC pavement project to date in the United States.
RCC pavements:
- Resist rutting
- Span soft localized subgrades
- Will not deform under heavy, concentrated loads
- Do not deteriorate from spills of fuels and hydraulic fluids
- Will not soften under high temperatures
Unique Mix, Unique Construction  RCC owes much of its economy to high-volume, high-speed construction methods.Large-capacity mixers set the pace. Normally, RCC is blended in continuous-mixing pugmills at or near the construction site. These high-output pugmills have the mixing efficiency needed to evenly disperse the relatively small amount of water used. Dump trucks transport the RCC and discharge it into an asphalt paver, which places the material in layers up to 9 inches (250 mm) thick and 42 feet (13 m) wide.  Compaction is the most important stage of construction: it provides density, strength, smoothness, and surface texture. Compaction begins immediately after placement and continues until the pavement meets density requirements. Curing ensures a strong and durable pavement. As with any type of concrete, curing makes moisture available for hydration—the chemical reaction that causes concrete to harden and gain strength. A spray-on membrane is typically used to seal moisture inside.  When appearance is important, joints can be saw cut into the RCC to control crack location. If economy outweighs appearance, the RCC is allowed to crack naturally. Once cured, the pavement is ready for use.
Economy. Performance. Versatility. For RCC, economy was the mother of invention. The need for a low-cost, high-volume material for industrial pavements led to its development.  Low cost continues to draw engineers, owners, and construction managers to RCC. But today's RCC owes much of its appeal to performance: The strength to withstand heavy and specialized loads; the durability to resist freeze-thaw damage; and the versatility to take on a wide variety of paving applications. From container ports to parking lots, RCC is the right choice for tough duty.
More from the Portland Cement Association about RCC: Features & Benefits of RCC Pavements RCC Resources Performance Chart Related RCC Links Research in Progress RCC FAQs
Cement Treated Base / Soil Cement:
Cement Treated Base (CTB) is a general term that applies to an intimate mixture or native soils and/or manufactured aggregates with Portland Cement Concrete and water. Other descriptions such as soil-cement, cement-treated aggregate base, cement-stabilized roadbed, and cement stabilized base are sometimes used.
CTB has several COST SAVINGS advantages over conventional bases. First, CTB provides a stiffer and stronger based than conventional base materials, which results in lower strains in the pavement surface. This both delays the onset of common surface distresses, including fatigue induced cracks, and prolongs the life of the pavement system. In addition, due to the higher loading capacity, the thickness of CTB layers can often be reduced in comparison to conventional bases while still carrying the same traffic. Finally, the use of local soils or in-place materials is often possible with CTB, which can significantly reduce material hauls.
From a construction standpoint, of the biggest advantages of CTB is the ability to maintain a working platform following periods of inclement weather. AG Peltz Group experienced this firsthand while working at the Honda Plant. In the early job phases construction delays were common as the existing dense grade base would become saturated and unworkable for days at a time. Honda personnel approached A.G. Peltz about co-developing a solution that would be both cost effective and allow construction targets to be maintained. This solution was 4” of CTB. AG Peltz mixed and placed the materials with the same equipment and process as conventional RCC. It took no time at all to discover that once the cement hydration process was underway and materials interlocked– the CTB layer was virtually impenetrable to water. AG Peltz was able to place RCC within 24 hours of excessive rainfall. Cost competitiveness was maintained as the base layer was reduced from 6” of aggregate base to 4” of CTB. The end result is that Honda now uses 4” of CTB under all paving areas.
AG Peltz has continued to grow its presence in placing CTB since the initial Honda project. They have completed projects with strict testing requirements, including high strength mixes for the Pensacola Airport (FAA Specifications) and lower strength mixes for the Alabama Department of Transportation (Soil-Cement). In each case, the use of local materials mixed with cement and water was more economical than hauling in select granular materials. Economy, quality, innovation – the AG Peltz way.
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