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Concrete densifying admixture

ConBlock CDA contains pure silicon dioxide dispersed in a proprietary liquid that densifies and waterproofs concrete. Against reference mix designs, users can anticipate a faster set with less bleed water and earlier strength gains, owing to accelerated cement hydration, plus higher 28-day compressive strength. The reduction in surface bleeding allows for faster finishing and a more durable slab or structure. Higher early strengths allow for faster form removal, saving time in the plant and at the job site, while reduced permeability improves resistance to sulfuric acid and other harmful chemicals.

ConBlock CDA has a 12-month shelf life in a dry environment with temperatures above 40°F, and is packaged in 5-gal. pails, 50-gal. drums or 264-gal. totes.

Concrete Sealants tested ConBlock CDA in an independent laboratory using the U.S. Army Corps of Engineers Standard CRD C48-92 to 200 psi for 28 days. Treated specimens did not allow water to pass. In addition, the agent reduced the water penetration of a 6,000-psi control concrete by 32 percent. Further studies indicate ConBlock CDA outperforms traditional crystalline powder admixtures as measured in ASTM C1585, Standard Test Method for Measurement of Rate of Absorption of Water by Hydraulic-Cement Concretes.

ConBlock CDA can be set up for automated dosing in most batch plants. Typical dosage is 22 ounces per 100 lbs. of portland cement, although certain mix designs and applications can warrant up to 40 ounces per CWT. As a liquid, the admixture improves safety by reducing the opportunity for release of silica-bearing powder into work areas. It suits cast-in-place or precast concrete specified for bridges and highways, parking structures, water containment tanks, foundations, tunnels, as well as a host of below-grade structures where watertight integrity is critical. ConBlock CDA joins the company’s full line of sealants, extruded sealing tapes, primers, wraps, waterstops, coatings, mastics, lubricants, surface hardeners, water repellents, and antimicrobial admixtures. ConSeal products are used to assemble and seal precast concrete pipes, manholes, box culverts, septic tanks, burial vaults, structures, buildings and components of all types. Concrete Sealants Inc., Tipp City, Ohio, 800/332-7325 or 937/845-8776;