RCC: Asphalt Pavement’s Good Cousin

We close this year Illinois centric: a December cover story on Prairie Material Sales’ roller compacted concrete pavement program follows a November cover feature on Ozinga Brothers Inc. and its fleet-wide conversion from diesel to compressed natural gas fuel. Synonymous with Chicago concrete, both producers warrant the attention.

Underpinning the Ozinga Bros. fleet fuel spec change are proven domestic resources assuring long-term supply of natural gas, coupled with global petroleum market fundamentals. As Ozinga Bros. addresses petroleum price volatility from an operational standpoint, its neighbor Prairie Material takes the market lead in promoting RCC pavement, whose competitiveness is directly tied to the instability of petroleum-derived asphalt binder prices.

With the exception of clay masonry units, RCC is unique among concrete products or structures with widely used alternative solutions: Its placing and finishing sequences mimic those of its main competing material. Asphalt contractors wishing to test RCC placement have an apples-to-apples comparison of delivery and labor variables to factor into future estimates or bids. On the procurement side, contractors can obtain RCC mixes from a transit or central mixed concrete plant operator, whose asphalt counterpart would be hard pressed to load up 9 yards of 3,500-psi concrete flatwork mix. More practical for the volume applications where RCC pavement has the most promise are portable mixer and conveyor assemblies that mainline manufacturers like Vince Hagan Co. and Stephens Mfg.—the latter in partnership with Sicoma North America—have developed to produce RCC in a dry or wet ready mixed plant alley.

Indiana ready mixed producers began using the Stephens/Sicoma unit three years ago; their promotion and field practice successes have helped set the table for Prairie Material and Illinois peers. For its first three years of RCC pavement mix deliveries, where volume totaled 2,000 to 3,000 cu. yd., Prairie Material tackled orders with central mixed equipment. With 2012 RCC pavement contracts requiring upward of 18,000 yd., it switched to a Hagan portable mixer and wet belt better suited to producing the ultra-dry material and charging primarily dump trucks, but also mixers on certain jobs.

Concurrent with Prairie Material’s RCC pavement push is a flurry of activity among allied industry groups. American Concrete Insitute Committee 327 is finishing a formal standard, 327.XR Report on Roller-Compacted Concrete Pavements, while the National Ready Mixed Concrete Association has scheduled a January 8/March 5 webinar themed “Roller Compacted Concrete: Your Third Choice for Pavement,” providing material and engineering perspectives.

To mirror a companion whitetopping project offering, American Concrete Pavement Association is preparing a microsite mapping major RCC pavement installations—launching in early 2013 with up to 200 initial click-through “points.” A year ago, the ACPA Strategic Board of Advisors approved a Roller Compacted Concrete Task Force aiming to identify challenges and opportunities for member contractors and ACPA allies adopting RCC. Short-term task force goals include growing product acceptance and market prospects through ACPA-led technology transfer/education plus promotional and technical support.

Officially launched in January 2012, the task force numbered 42 at year’s end, members including representatives from 15 contractors plus nine chapters or state groups, eight cement companies, five equipment manufacturers and three materials producers. Subgroups are dedicated to the three short-term task force goals and assisted in 2012 deliverables that have included a mid-June RCC Workshop and late-August RCC Equipment Considerations webinar. Goals for 2013 were to be determined as the RCC Task Force convened during the late-November ACPA Annual Meeting.

Thanks to the industry’s good ground game in the Midwest and other regions, RCC pavement joins a long list of value propositions concrete producers and allied groups can bring to public and private markets in the new year.