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40-27 BUILDING PRECAST CONCRETE <br />BRPH ARCHITECTS -ENGINEERS, INC. <br />2.7 INSULATED PANEL ACCESSORIES <br />A. Polyisocyanurate Board Insulation: ASTM C 591, Type I, 1.80 lb/cu. ft.; unfaced; <br />square edges; with thickness of 2 inches. <br />B. Wythe Connectors: Glass -fiber and vinyl -ester polymer connectors, Polypropylene pin <br />connectors, Stainless -steel pin connectors, Bent galvanized reinforcing bars or <br />galvanized welded wire trusses manufactured to connect wythes of precast concrete <br />panels. <br />2.8 CONCRETE MIXTURES <br />A. Prepare design mixtures for each type of precast concrete required. <br />1. Limit use of fly ash to 20 percent of portland cement by weight. <br />B. Design mixtures may be prepared by a qualified independent testing agency or by <br />qualified precast plant personnel at precast concrete fabricator's option. <br />C. Limit water-soluble chloride ions to maximum percentage by weight of cement <br />permitted by ACI 318 or PCI MNL 117 when tested according to <br />ASTM C 1218/C 1218M. <br />D. Normal -Weight Concrete Mixtures: For insulation panels, proportion face and backup <br />mixtures or full -depth mixtures, at fabricator's option by either laboratory trial batch or <br />field test data methods according to ACI 211.1, with materials to be used on Project, to <br />provide normal -weight concrete with the following properties: <br />1. Compressive Strength (28 Days): 5000 psi minimum (for both solid and <br />insulated panels). <br />2. Maximum Water-Cementitious Materials Ratio: 0.45. <br />E. Water Absorption: 6 percent by weight or 14 percent by volume, tested according to <br />PCI MNL 117. <br />F. Add air -entraining admixture at manufacturer's prescribed rate to result in concrete at <br />point of placement having an air content complying with PCI MNL 117. <br />G. When included in design mixtures, add other admixtures to concrete mixtures <br />according to manufacturer's written instructions. <br />2.9 FABRICATION <br />A. Cast -in Anchors, Inserts, Plates, Angles, and Other Anchorage Hardware: Fabricate <br />anchorage hardware with sufficient anchorage and embedment to comply with design <br />requirements. Accurately position for attachment of loose hardware, and secure in <br />place during precasting operations. Locate anchorage hardware where it does not <br />affect position of main reinforcement or concrete placement. <br />C06922.001.00 03 45 00 - 6 , <br />05-22-14 <br />