Company’s new line of carbon dioxide-based pH control systems features the non-fouling high efficiency Dif-Jet gas injector. The technology combines patented gas injectors that transfer C0₂ into water to produce carbonic acid. The injectors have 90 percent-plus efficiency and are installed on distribution and flow designs for easy control and mixing. Side stream injection is also available.
A volumetric concrete equipment leader, Iowa-based Cemen Tech Inc. unveiled its C860 mixer at the World of Concrete in Las Vegas last month, spotlighting an electronic control panel and GPS tracking solution among key new features. The model offers customers “a design that will make the operation easier and allow their drivers to pour concrete in a more efficient way,” notes Director of Sales & Marketing Mark Rinehart.
A manufacturer of asphalt paving machines for Caterpillar dealers world wide, whose contract production log includes a decade of concrete mixer drum system deliveries, has expanded its branded lines. After acquiring a mixer system design and intellectual property, Knoxville, Iowa-based Weiler Inc. is now offering complete truck models, showing its first vehicle at the Caterpillar World of Concrete 2015 booth.
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World of Concrete 2015 outdoor exhibits proved well worth negotiating for attendees eager to observe a different take on the U-shaped assembly through which hundreds of millions of cubic yards of ready mixed flow annually.
Replacement of recycled concrete aggregate (RCA) for natural coarse aggregate by up to 45 percent by volume had no significant effects on any of the concrete properties studied, indicating high-quality RCA can be used as a replacement for a portion of the coarse natural aggregates in new portland cement concrete pavements. That’s what Haifang Wen, Ph.D., P.E., Washington State University; David I. McLean, Ph.D., P.E., Colorado State University; and, Kim Willoughby, Washington State DOT, report in their 2015 TRB paper, Evaluation of Recycled Concrete as Aggregates in New Concrete Pavements.
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A refined self-consolidating concrete (SCC) mix was developed to achieve the high workability needed for faster concrete discharge and finish, and attain the Florida Department of Transportation six-hour strength requirement of 2,200 psi (15 MPa) for concrete slab replacements, report Jamshid Armaghani, Ph.D., P.E., Global Sustainable Solutions, Gainesville, Fla.; Kamal Tawfiq, Ph.D., P.E., and Steven Squillacote, FAMU-FSU College of Engineering, Tallahassee; and, Michael Bergin, P.E., State Materials Office, Florida DOT-Gainesville, in their 2015 TRB paper, Accelerating Slab Replacement Using Self-Consolidating Concrete.
Research in Mississippi shows that portland cement/limestone blends (PLC) result in notable compressive strength improvements in mixtures with high Class C fly ash replacement versus conventional Type I portland cement, say Jay Shannon and Dr. Isaac L. Howard, P.E., Mississippi State University, and V. Tim Cost, P.E., F.ACI, and Wayne M. Wilson, P.E., Holcim (US) Inc., in their 2015 TRB paper, Benefits of Portland-Limestone Cement for Concrete with Rounded Gravel Aggregates and Higher Fly Ash Replacement Rates.
Interground limestone/cement blends are appropriate for all uses in the Pelican State, say Tyson D. Rupnow, Ph.D, P.E., and Patrick J. Icenogle, P.E., Louisiana Transportation Research Center, Baton Rouge, in their paper, Louisiana’s Laboratory Experience with Type IL Portland Cement.
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Glow-in-the-dark concrete took the stage with new research in self-consolidating concrete, portland cement/limestone blends, and recycled concrete aggregates in ready mixed concrete, and it’s all illuminating the future of cast-in-place.
The National Ready Mixed Concrete Association’s 19th Annual Ready Mixed Concrete Delivery Professional Driver of the Year program recognizes two industry veterans from a pool of outstanding nominees across the country. The NRMCA Operations, Environmental and Safety Committee assembled a panel of judges to weigh nominees’ competence, driving skills, number of years without an on- or off-road accident, and colleague or customer testimonials. Judges awarded Driver of the Year honor to Eastern Concrete Materials’ Edward “Eddie” Rieper and Runner-Up honor to Concrete Supply Co.’s Henry “Pete” Scarborough. NRMCA-affiliated Truck Mixer Manufacturers Bureau will award Rieper $5,000, and Scarborough $1,000. Both drivers will be formally honored this month during the NRMCA Annual Convention in Orlando.