Finisher, CIM student crews experience W/C-friendly troweling aid first hand.
Day1 is sprayed on fresh concrete in small quantities and troweled into the surface. It lubricates, making troweling easier, reducing drag, and minimizing blade wear and operator fatigue. Its main ingredient, colloidal silica, reacts with the lime by-product of cement hydration, and turns it into additional cement paste; with more "cream" for the finisher to use, the slab is easier to finish and has a potentially smoother surface.
As colloidal silica agent, Day1 seals the surface, slowing evaporation, which extends the cement hydration window and finishing time 15-45 minutes without weakening the slab or adding excess water to the mix. In field trials, finishers used 75 percent less total liquid with Day1 vs. finishing with water. They need less time to close the surface under normal conditions, but can have more time under adverse conditions. The troweling aid's additional cementitious material strengthens the surface.
Vancouver, Wash.-based Lythic Solutions, founded in 2008 by veterans of industrial and decorative stabs on grade, formulated Day1 with an eye to helping crews counter the effects of wind, heat, low humidity and sun exposure-variables that can prevent proper finishing or lead to a finished slab's lack of smoothness, unevenness and checking or crazing. Their new product increases workability and imparts water-retention characteristics comparable to liquid membrane-forming curing compounds.
Slab finishing demonstrations at this year's World of Concrete were staged in the Las Vegas Convention Center Gold Lot. Concrete supplied by Nevada Ready Mix Corp. was placed by MTSU CIM students, who worked alongside finishing professionals from Carey Concrete and Scott's Concete of Camdenton, Mo. A ready mixed producer and early Day1 adopter, Scott's Concrete has incorporated the troweling aid as a value-added product, loading 5-gal. pails on slab pour-bound mixers.
The World of Concrete demonstration was an extension of Lythic-sponsored testing by the MTSU CIM Department, in conjunction with the Tennessee Concrete Association. Pre-show and Gold Lot testing served as the first steps toward developing performance measurements and standards for concrete slab troweling aids. The Las Vegas testing saw CIM student teams and volunteer flatwork professionals handle three pours on each of the first three days of the show. Slabs treated with Lythic Day1 and Curing Agent were finished alongside slabs finished conventionally using extra water, and control slabs finished 'dry.' The results demonstrated a significant, measurable effect of the troweling aid at increasing the work window, with finishers commenting that the spraying of Dayl compound on test slabs made their jobs easier and improved end results.
"The [dry] first slab 'went' real quick, got hard 'way too fast' and it wouldn't fill in any of the rock pockets of any of the holes," says Miles City, Mont., finisher Curtis Kountz. "The second slab with water, it went real smooth, but you could tell the water was just filling in the holes that were there but it wasn't actually putting any cement into the holes. [The third slab] with the Lythic, it brought the cream back up, filled in all the holes and made it nice and easy to power trowel. It was hard underneath, but the top 1/8th inch was really workable. I had plenty of time to work with it."
Test methods for measuring troweling aid performance will enable contractors to select effective materials that will not compromise the concrete. MTSU CIM Director Dr. Heather Brown, who is overseeing the Lythic program, notes that evolution of an ASTM or similar standard could take 12-18 months or more.
Day1's long-term benefits, Lythic officials note, include strengthening the concrete surface; increasing its water-repellence; slowing evaporation to foster continuing slab curing; and, reducing the potential for ASR-driven pop-outs. The product has been third-party laboratory tested to meet water-retention requirements of a liquid membrane-forming curing compound per ASTM C156 Standard Test Method for Water Loss (from a Mortar Specimen) Through Liquid Membrane-Forming Curing Compounds for Concrete, even though Day1 forms no membrane.
Other properties that may be tested in the future include freeze-thaw resistance, chloride penetration, curling resistance, and the effects of perpetual curing. Day1 is packaged as a concentrate to minimize freight costs and environmental impacts. It is available from Lythic distributors and direct from the manufacturer, and will soon be available from Solomon Colors (note companion sidebar).--Lythic Solutions, 360/772-2065; www.lythic.net.
SOLOMON COLORS, LYTHIC SOLUTIONS INK DISTRIBUTION DEAL
Solomon Colors Inc. has added a Line of slab polishing and finishing agents to its namesake brands. Following a distribution deal announced at the World of Concrete, the company will begin stocking Lythic Solutions products at strategic Locations across the U.S. and Canada, which in turn supply more than 1,000 distributors or ready mixed producers. Each of Solomon's 24-member sales team will represent the flagship and Lythic lines, along with the slab restoration Contrazzo brand.
The distribution plan includes the Day1 Troweling Aid, which Like the rest of the Lythic product Line is based on colloidal silica, a highly pure form of silica that is more chemically efficient than the silicates used in conventional densifters, and virtually eliminates the addition of discoloring metallic salts to the concrete. Colloidal silica's unique bonding properties, including bonding to itself, build strength cumulatively and make it highly effective for densifying and protection becoming what Lythic Solutions contends is a perfect complement to integrally colored concrete and other decorative treatments. Colloidal silica products are less caustic than their silicate counterparts, therefore safer to handle and more environmentally friendly.
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|Title Annotation:||INNOVATIONS REPORT|
|Date:||Mar 1, 2013|
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