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2014SumShotcreteEMag

Association News Get Out Your Cameras and Submit transport properties—and, by inference, the inherent durability Your Outstanding Shotcrete Projects and service life prediction characteristics—of cast concrete and ASA is now accepting entries for cast wet-mix concrete compared to companion shot wet-mix its 10th Annual Outstanding Shot - shotcrete and shot dry-mix shotcrete. This research was pro- crete Project Awards. Entries are posed to specifically address one of the most difficult challenges due by October 1, 2014. These annual currently facing the shotcrete industry: How does the durability project awards recognize excel- of shotcrete (both wet- and dry-mix) compare with the dura- lence and innovation in projects in bility of an equivalent cast-in-place concrete mixture? which the application of shotcrete Shotcrete is a method of placing concrete. The question still has played a significant role. arises, however, whether the placement method affects the The ASA award program offers you and your organization transport properties in shotcrete. Such questions are frequently unique and distinguished exposure within the shotcrete industry. asked by DOT/MOTs, structural engineers, architects, owners, In addition, the awards program and the annual awards issue as well as materials suppliers. Meanwhile, the challenges in of Shotcrete magazine are important tools used to inform and proving the durability of shotcrete compared to cast concrete educate the construction world, providing an exciting real- have become more difficult. The shotcrete industry has even world demonstration of the many benefits and advantages of encountered DOT specifications containing specific provisions placing concrete via the shotcrete process. against the use of shotcrete and highlighted their opinion that Use the streamlined and simple online application form shotcrete is not as durable as cast-in-place (CIP) concrete. This to submit your project today at http://shotcrete.org/pages/ research aims to directly address such claims. membership/project-awards.htm. Research Program Now Accepting ASA Graduate Transport properties in concrete are fundamental in under- Scholarship Applications standing the durability and expected service life of concrete and shotcrete and include: ASA is now accepting applications • Absorption; for Graduate Scholarships for the • Diffusion; 2014-2015 academic year. Up to • Permeability; three $3000 (USD) awards are • Sorptivity; and available for the 2014-2015 aca- • Wicking. demic year to those pursuing a This study should provide a quantifiable statement as to how graduate degree in an accredited the quality of cast concrete and cast wet-mix shotcrete compares college or university within either the United States or Canada. to shot wet- and dry-mix shotcrete and how this should affect The purpose of the ASA Graduate Scholarship Program is durability and predicted service life. to attract, identify, and assist outstanding graduate students The testing program includes the following mixture types: pursuing careers in the concrete industry with a significant cast concrete, cast wet-mix, shot wet-mix, and shot dry-mix. interest in the shotcrete process. Based on essays, submitted The concrete and shotcrete mixtures were all designed to meet data, and references, the ASA Scholarship Committee will ACI and Canadian Standards Association (CSA) requirements select scholarship recipients who appear to have the strongest for chloride and freezing-and-thawing exposure (that is, min- combination of interest and potential for professional success imum compressive strength of 5075 psi 35 MPa at 28 days, in the shotcrete industry. 0.45 maximum water-cementitious material ratio w/cm and Winners will be asked to submit a brief summary of their suitable air entrainment). concrete-related research for publication in ASA’s Shotcrete The current state-of-the-art for evaluating and modeling the magazine. Each ASA Graduate Scholarship Award is paid in durability and service life prediction of shotcrete/concrete, as one installment of $3000 USD directly to the student’s educa- adopted by the U.S. Navy and other agencies, involves the use tional institution. of STADIUM software for service life modeling. STADIUM Applications and all required documents must be received is proprietary software that models the durability of shot - by 5:00 p.m. EST on Monday,November 3, 2014. All application crete/concrete based on the time to initiation of corrosion in information and requirements can be found at http://shotcrete. reinforcing steel considering the shotcrete/concrete cover. Tests org/pages/education-certification/grad-scholarships.htm. required to provide input information for STADIUM modeling ASA Sponsors Research on the • Porosity (modified ASTM Test Method C642);and these tests are typically performed on test samples at 90 days: Durability and Service Life of Shotcrete • Ionic Migration Test (modified ASTM Test Method C1202); ASA has generously contributed $20,000 to LZhang Consulting and & Testing Ltd. in support of a research project comparing the • Drying Test (moisture migration assessment). 58 Shotcrete • Summer 2014


2014SumShotcreteEMag
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