Day1 from Lythic Solutions, a new type of troweling aid and curing agent, successfully extends concrete finishing time and reduces surface drying, according to tests performed at Middle Tennessee State University (MTSU).
"A product that increases contractor productivity without affecting concrete quality is a game changer," says Lythic President David Loe, "and it is worth testing scientifically."
Day1 is applied to the slab in small quantities during troweling, and allows the finisher to close the slab more easily without needing to add water to the surface. Day1 inhibits drying due to heat, wind, or other adverse conditions, and does not weaken the concrete. The current test series may prove that, in fact, Day1 actually strengthens the surface.
The research is being conducted by staff and students of the MTSU's Concrete Industry Management Program. It is a first step toward being able to quantify the effectiveness of troweling aids. "Power troweling aids have yet to be defined by ASTM or ACI," explains Loe. "There is currently no quantitative test method to assess a product's claim to effectiveness during power troweling, making this test something of a trail-blazing effort." The first phase of testing proved to be a validation for Lythic's Day1.
"The research team placed a large slab, and divided it into separate work areas," Loe elaborates. "An experienced concrete contractor finished the surface using a walk-behind power trowel, working under three different conditions." One protocol required finishing without any troweling aid or additional water. The second condition allowed water to be added whenever the finisher wanted it during power-troweling. The third condition allowed Day1 to be added, but not water.
Researchers monitored the power trowel's engine RPM and blade setting, and the operator's comments describing resistance. The most significant measure was the ability to finish the slab properly. To evaluate the effect of the troweling aid on concrete's performance, researchers will also examine cores and conduct durability tests after the slab has cured the required 28 days.
Contractors commonly spray water onto wet concrete during finishing (sometimes called "blessing the slab") to draw up the "cream" that helps close up the surface and create a smooth finish. They may also use water to try to "buy time" if the surface is setting too quickly. However, adding water changes the chemical balance at the surface, weakening it and causing dusting and other problems.
Based on eco-friendly colloidal silica, Day1 is a liquid that is sprayed in small quantities onto the concrete during finishing. Day1 chemically reacts with the concrete to close the pore structure, which slows evaporation. It also lubricates troweling: when Day1 was sprayed on during the MTSU test, the power-trowel could be heard speeding up. Day1 reduces operator fatigue, and wear-and-tear on the equipment.
In prior field tests, Day1 was subjectively observed to extend finishing time anywhere from 15 up to 45 minutes. In conditions of wind, low humidity, or heat, that can make the difference between finishing successfully and "losing the slab." Contractors field-testing it said it strengthens the surface, eliminates dusting, and helps prevent checking and crazing. They described Day1 as, "like having an extra finisher on the jobsite."