June 15, 2010
CTS Cement Manufacturing Corp. — the largest manufacturer of specialty fast-setting hydraulic cement and shrinkage compensating cement – has been awarded a five-year contract with the Department of Defense for the supply of concrete repair material.
In fulfillment of the contract, CTS Cement will supply its Rapid Set cement, a rapid-hardening hydraulic cement the company developed and manufactures. Chris Davis, CTS Northeast Manager, said the chemistry of this type of cement makes high early strength gains possible, which is ideal for the military’s need of a repair material for runways, roadways, buildings, or any other areas where high-strength concrete is needed.
According to a study by engineering firm Wiss, Janney, Elstner Associates, Inc. of Northbrook, Ill., when the cement hydrates with the addition of water, it forms a compound called ettringite. This crystalline compound forms quickly, producing rapid strength gains. The cement’s high uptake of free water during hydration contributes to a low shrinkage rate, Lab tests demonstrated an average 28-day shrinkage of 0.027 percent for concrete produced with rapid-curing cement.
For example, in California, Rapid Set concrete has proven to achieve the necessary traffic flexural strength requirement of 2.8 MPa (406 psi) in less than two hours and often within one hour, according to a written press statement from CTS.
The Caltrans 7-day flexural strength requirement of 4.2 MPa (608 psi) is typically achieved within eight hours.
“After many years of military testing, this contract gives the Department of Defense a high quality, low cost solution to all of their concrete repair requirements,” Davis said in a written statement.