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fire-resistance ratings of that Design provided the unit weight
of the concrete meets the requirements of Design D916.”
(Note: UL allowed the supplier of the concrete product to be
fire tested to indicate the material properties. As a result, some
of the fire-resistance ratings call for concrete with a total air
content, an air-entrained content and an entrapped-air content.
Some specifiers use the same terms as UL on the drawings,
making the air content intent unclear.)
Many ASCC concrete contractors have worked with
suppliers that can provide pumpable, lightweight concrete
mixtures with air contents less than 3% while meeting density
and fire-rating requirements.
ASCC Position Statement #44 recommends measuring air
content of non-air-entrained concrete so both the ready mixed
concrete producer and the concrete contractor know what is
being delivered and can make appropriate adjustments.
Without measuring, all parties are guessing as to what is
delivered and what is finished. ASCC believes that measuring
air content and using that information provides a benefit to
ASCC Finishing Subcommittee: Steve Lloyd, Lloyd
Concrete Services, Inc., and David Somero, S&S Concrete
Floors, Inc., Co-Chairs; Bryan M. Birdwell, Structural
Services Inc.; Joseph A. Daczko, BASF Corporation; Greg K.
Fricks, The Fricks Company; John Hawkins, Sundt; Myron J.
Hillock, Somero Enterprises, Inc.; William “Duck” Lloyd,
Lloyd Concrete Services, Inc.; Jesse Long, PROCON, Inc.;
Rusty Maglionico, The Euclid Chemical Company; Matt
Poppoff, Poppoff, Inc.; Jim Schibley, Sundt; Michael J.
Somero, Ace Avant Concrete Construction Co. Inc.; Michael
L. Tholen, ACI; and Ben Wiese, Multiquip Inc., Members; and
Bruce Suprenant, ASCC Liaison.
1. Bimel, C., “Is Delamination Really a Mystery?” Concrete
International, V. 20, No. 1, Jan. 1998, pp. 29-34.
2. ACI Committee 302, “Guide to Concrete Floor and Slab
Construction (ACI 302.1R-04),” American Concrete Institute,
Farmington Hills, MI, 2004, 76 pp.
3. ACI Committee 302, “Guide to Concrete Floor and Slab
Construction (ACI 302.1R-15),” American Concrete Institute,
Farmington Hills, MI, 2015, 76 pp.
4. Lankard, D.R., “Air Entrainment and Delaminations,” Concrete
International, V. 26, No. 11, Nov. 2004, pp. 21-30.
5. RILEM Technical Committee TC 268-SIF, “Surface Delamination
of Concrete Industrial Floors and Other Durability Related Aspects
Guide,” V. Pollet editor, RILEM, Paris, France, 2017, 62 pp.
6. Ahal, D.C.; McCall, C.; and Suprenant, B.A., “Delamination of
Trowel-Finished Lightweight Concrete Slabs,” Concrete International,
V. 29, No. 6, June 2007, pp. 39-44.