shear capacities exceeding 80 percent of their static capacities, when tested in accordance with ICBO ES AC01.
Connector shall have been shown, by testing laboratory certified by ICBO ES, to resist 300 lb tension loads for over 90 minutes when embedded in 3 inches of concrete and subjected to a furnace exposure per Section 7.8 of ASTM E1512.
Upon request, connector supplier shall provide documentation of alkali resistance of connector and long-term shear capacity of connector.
Coefficient of thermal expansion: 5x10-6 in/in/°F, nominal.
Thermal Conductivity: 2.1 Btu/ (°F•ft2•h) per inch of length.
Proven accelerated aging testing. Provide reports showing compliance with accelerated aging equivalent to up to 100 years of service in concrete.
Prepare design mixes to match Architect’s sample for each type of concrete required.
Revise subparagraph below if fly ash, blast furnace slag, or silica fume are not permitted. Revise percentage to suit Project.
1. Limit use of fly ash and granulated blast-furnace slag to 20 percent replacement of portland
cement by weight; metakaolin and silica fume to 10 percent of portland cement by weight.
Design mixes may be prepared by a qualified independent testing agency or by qualified precast plant personnel at architectural precast concrete fabricator’s option.
Limit water-soluble chloride ions to the maximum percentage by weight of cement permitted by ACI 318 (ACI 318M) or PCI MNL 117 when tested in accordance with ASTM C1218/C1218M.
Architectural precast concrete units may be manufactured with a separate “architectural” face mix and a “structural” backup mix. Face and backup mixes should have similar shrinkage and expansion coefficients. Similar water-cementitious materials ratios and cement-aggregate ratios are recommended to limit bowing or warping.
Normal-Weight Concrete Face and Backup Mixes: Proportion mixes by either laboratory trial batch or field test data methods according to ACI 211.1, with materials to be used on project, to provide normal-weight concrete with the following properties:
Retain subparagraph below or revise to suit Project. Higher-strength mixes may be available; verify with fabricators.
Compressive Strength (28 Days): 5000 psi (34.5 MPa).
A water-cementitious materials ratio of 0.40 to 0.45 is usual for architectural precast concrete.