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construction test panels (the ideal approach) or from the shotcreted structure itself (for particular cases where in-place quality is questionable). The outcome of this evaluation of core quality is a qualitative judgment such as “good” or “fair.” The hope of the committee is to have this methodology published as a Technical Note (a short standalone ACI technical document) to facilitate its updating and revision. The second part is a dedicated section in the Evaluation document on the Acceptance Criteria that is based on a number of difficulty levels, which address many aspects of the jobs such as section thickness, reinforcement layout, orientation, and need for certified nozzleman. This section of the Evaluation document will therefore guide the engineer in identifying the Difficulty Level related to the work in progress (a jobsite may present several different difficulty levels) and in selecting the Quality Level the engineer is willing to work with. In effect, the engineer is creating project-specific acceptance criteria. Although briefly hinted at previously, it is noteworthy to mention that the Evaluation document being developed will also include a complete section on mockup panels and preconstruction trials, an increasingly popular qualification method. The objective here is to illustrate what has been successfully done in the past on projects, and then point out what information can be gained from these tests. Fibers and Underground Our two remaining subcommittees are working on 506.5R-09, Guide for Specifying Underground Shotcrete, and 506.1R-08, Guide to Fiber-Reinforced Shotcrete. Although slightly less impacted by the ongoing effort, they are nonetheless both in the process of being reapproved and the com- mittee members are hard at work revising them to make sure they reflect the most recent advances and good practices. Conclusions ACI Committee 506, Shotcreting, is busy and actively working on offering the most useful and complete document library for the entire shotcrete industry. With the rewriting and revision of our documents to reflect the most recent changes in the industry, the goal to make them coherent and synchronized across the whole library is well under way. As we look toward the future, we are also actively working on extending shotcrete acceptance into the concrete-specific Codes and standards that can benefit from incorporating shotcrete placement for many types of structural concrete construction. Marc Jolin, FACI, is a Full Professor in the Department of Civil and Water Engineering at Laval University. He received his PhD from the University of British Columbia, Vancouver, BC, Canada, in 1999. An active member of Centre de Recherche sur les Infrastructures en Béton (CRIB), he is currently involved in projects on service life, reinforcement encasement quality, new admixtures, and rheology of fresh shotcrete. Jolin is an ASA member; an ACI Examiner for Shotcrete Nozzleman Certification (wet- and dry-mix processes); Chair of ACI Committee C660, Shotcrete Nozzleman Certification; and Chair of ACI Committee 506, Shotcreting. 24 Shotcrete • Summer 2016


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