Grace Construction Products reports that its Strux 90/40 synthetic macro fiber product has received Underwriters Laboratory classification [CBXQ.R13667]
Grace Construction Products reports that its Strux 90/40 synthetic macro fiber product has received Underwriters Laboratory classification [CBXQ.R13667] as a welded wire mesh (WWM) alternative or companion in composite metal deck floor ceiling designs. The UL rating covers 1-, 1.5-, and 2-hour fire exposure for D700, D800 and D900 floor ceiling designs using Strux 90/40 Û 90 signifying the aspect ratio and 40 the length in mm. Grace’s fire testing has coincided with the 2006 ANSI/Steel Deck Institute C1.0 Standard for Composite Steel Floor Deck recognizing synthetic macro fibers as suitable replacement for temperature and shrinkage reinforcement. The use of synthetic macro fibers at a minimum 4 lb./yd. addition rate is an alternative to both WWM and steel fibers at a minimum addition rate of 25 lb./yd.
The UL rating and ANSI/SDI C1.0 Standard code revisions offer engineers and contractors construction options with significant labor and material savings when measured against conventional concrete, WWM and steel deck designs. On a five-story office building with 20,000-sq.-ft. floor plate, Grace cites a potential $14,000 to $20,000, or 32 percent, savings using a Strux specification versus WWM for temperature and shrinkage reinforcement. In that example, the building owner and contractor would realize additional savings and a faster concrete construction schedule from the elimination of labor involved in mesh placement, assuming a four- to five-man crew logging 10,000 sq. ft./day.
Projects where the Strux 90/40 spec has been chosen for temperature and shrinkage reinforcement in lieu of WWM include a) Cristo Rey Jesuit High School and Colin Powell Youth Center in Minneapolis, where Aggregate Industries supplied contractor Ryan Cos. 1,000 yd. for about 66,000 sq. ft. of floor plate; and, b) NOAA Office and Laboratory in Radio Station, N.C., where S.T. Wooten supplied contractor Joyce & Associates 135 yd. for a single level of elevated slab. Current composite concrete and steel deck projects carrying a Strux 90/40 spec include several hospitals, offices, municipal, educational, and mid-rise buildings.
Strux 90/40 comprises high-tenacity, polyolefin monofilaments, engineered to impart toughness, impact and fatigue resistance in concrete. The fibers disperse evenly and rapidly throughout the concrete matrix, Grace engineers note, offering many advantages including reducing or eliminating crack potential, maintaining post-crack load-carrying capability, and plastic shrinkage protection. The product has been used for over five years in slab-on-grade applications, precast, and structures in marine environments. Û www.graceconstruction.com