Concrete Products covers the issues that attract producers of ready mixed and manufactured concrete focusing on equipment and material technology, market development and management topics.
Issue link: https://cement.epubxp.com/i/64524
NEWS SCOPE READY MIXED U.S. Concrete's rapid drying concrete advances moisture-sensitive slab practice USC Technologies, Inc., bills its Aridus Rapid Drying Concrete as the first ready mixed solution for preventing floor cover- ing failure, an industry-wide problem that costs millions of dollars an- nually in damage, downtime, repair and replacement. The proprietary mix from the subsidiary of Texas-Based In a Moisture Vapor Evaporation Rate (MVER, top) test, an Aridus specimen reached a flooring installation-safe MVER level at least five times faster than a control specimen of conventional concrete. Specifications for common flooring systems typically call for an MVER of 3 lb./1,000 sq. ft./24 hours at application in order for a warranty to be valid. Under some site condi- tions, USC Technologies notes, conventional concrete slabs never attain the MVER threshold. U.S. Concrete Inc. can attain in 30 days or less—or three times faster than conven- tional concrete—the 75 percent internal relative humidity level increasingly refer- enced as a target for flooring covering ap- plication on new concrete slabs. Aridus test specimens have also exhibited strong performance for other benchmarks affecting floor-covering specifications: moisture vapor evaporation rate five times faster and (post-rewetting event) redrying rate four times faster when measured against conventional concrete controls. Properties the value-added mix imparts in finished slabs equate to what USC Technolo- gies notes is a faster and more effective floor covering installation that helps a) CONCRETE SLAB FLOORING VAPOR BARRIER To gauge the MVER after a rewetting event—mim- icking exposure to rain new slabs might encounter in the field—USC Technologies researchers ponded Aridus and conventional concrete specimens with a ¼-in. of water for 24 hours (above), then ob- served the number of days each required to attain a floor covering application-ready MVER threshold of 3 lb./1,000 sq. ft./24 hours. The Aridus speci- men reached it in 16 days, while the conventional control exhibited MVER of 3.7 lb/1,000 sq. ft./24 hours past 60 days. keep critical projects, in wet or dry climates, on schedule; and, b) significantly reduces owners', designers' and builders' risk of proj- ect delay and failure liabilities. "Aridus is an extremely innovative concrete tech- nology and the result of over five years of research and development," says U.S. Concrete CEO William Sandbrook. "Our objective was to address the prob- lem from a concrete standpoint and pro- vide a more reliable and long-term solution to moisture problems in concrete floors." "Current solutions are mainly late stage treatments or topical solutions that basi- cally seal the moisture in. The moisture re- mains [as] a potential problem that can emerge," adds Vice President of Sales & Marketing Wally Johnson. The product joins other branded, project-specific mixes USC Technologies has developed for U.S. Concrete's mid-Atlantic, Texas and Califor- nia operations, he adds, along with li- censed or approved ready mixed producers across the country (note Stego sidebar). Bubbling and seam failure are common problems for floor coverings applied on slabs exhibiting Mois- ture Vapor Evaporation Rates above 3 lb./1,000 sq. ft./24 hours. USC Technologies shows how a vapor barrier can help eliminate ground moisture migration but have no effect on flooring covering dam- age-prone moisture within the slab itself. STEGO INDUSTRIES MAKES THE GRADE AS NAMED EXCLUSIVE ARIDUS SALES PARTNER U.S. Concrete announced an agreement in April whereby San Clemente, Calif.-based Stego Industries LLC, a key player in below-slab vapor barriers, becomes exclu- sive channel partner to market and sell Aridus Rapid Drying Concrete. The agree- ment creates significantly increased op- portunities to reach the architectural and engineering communities and showcase the benefits of Aridus as a game-changing solution to concrete slab moisture prob- 12 | MAY 2012 lems, U.S. Concrete affirms. "We are confident this strategic partner- ship will provide the level of expertise needed to address [slab] moisture-related problems facing the construction design and engineering community," says U.S. Concrete's Wally Johnson. "For more than a decade, we have pro- tected the most sensitive sites in North America by educating the concrete com- munity about keeping slabs free of mois- ture," affirms Stego CEO Paul Blasdel. "Aridus will be a game-changing comple- ment to this mission by providing a way for builders to get their concrete dry much faster than traditional ready mixed." "We recognize the value of Aridus as the first ready mixed concrete solution to an industry-wide problem," adds Stego Chief Operations Officer Matthew Blasdel. "Aridus focuses on preventing moisture problems in concrete floors before they arise." WWW.CONCRETEPRODUCTS.COM