J&S Concrete Delivers First Slab Carrying New Fiber Spec

A 200-yd. order ready-mixed producer J&S Concrete dispatched to a warehouse site marks the North American debut of Raditeck AC 60 fiber. Ft. Mill, S.C.,

CP STAFF

A 200-yd. order ready-mixed producer J&S Concrete dispatched to a warehouse site marks the North American debut of Raditeck AC 60 fiber. Ft. Mill, S.C., contractor Zimmer & Sons approved the specification following assurances from J&S and Raditeck distributor, Ft. Lee, N.J.-based ICF Mercantile, that AC 60 curtails plastic shrinkage cracking and Û when mixed for five minutes or longer Û disperses evenly in the matrix without surface protrusion. The producer dosed mixes at 1-lb./yd., loading water-soluble bags immediately upon trucks’ charging alley exit. The minimum mixing time was easily met, as the Lancaster, S.C., transit mixed plant is about 12 miles from the Ft. Mill site.

After seeing the fibers’ tendency to settle just below the slab surface, Zimmer crews observed their distribution and toughness-imparting characteristics upon breaking a hardened concrete specimen. The contractor indicated the AC 60-dosed mixes had performed better than other fibrous concrete it had placed on nine prior slabs for neighboring industrial park jobs. The fiber’s specific gravity (1.17 g/m versus water’s 1.00 g/m) is reflected in improved matrix distribution and absence from finished surfaces. Û ICF Mercantile, 201/482-8032; www.icfmercantile.com