METNA CO — Department of Defense SBIR Phase I: AF161-002

Description

ABSTRACT: A new class of hydraulic cement and concrete materials will be developed with desired fresh mix rheology and set time to expedite placement of concrete pavements using common practices, and with favorable hydration kinetics to enable opening of pavement to heavy traffic within one hour after placement. The new materials also provide desired economics, sustainability, heat of hydration, fatigue life, dimensional stability and long-term durability. They can be tailored towards different climatic conditions and construction practices. Three primary principles will be adopted towards development of the new materials: (i) hybrid cement chemistries supplemented with compatible admixtures; (ii) optimum particle size distribution and packing of hydraulic cement, and also aggregates and all granular matter; and (iii) mechanochemical processing to control the dissolution and reaction rates of mineral constituents. The proposed Phase I project will develop and optimize alternative hydraulic cement chemistries, devise advanced concrete mix design procedures, and identify admixtures that are compatible with the selected hybrid cement chemistries. Comprehensive performance, cost, sustainability and safety investigations will be conducted in order to identify the most promising hydraulic cement and concrete materials for further development. The competitive merits and commercial potential of the new materials in pavement repair applications will be verified.; BENEFIT: The new hydraulic cement and concrete materials enable expedient placement of the pavement capping layer, and opening of airfield and highway pavements to heavy traffic within one hour after placement. They offer desired fresh mix workability and set time, that can be tailored to suit different climatic conditions and construction practices. Enhanced fatigue life, abrasion resistance, dimensional stability, resistance to restrained shrinkage cracking, and long-term durability are also among the advantages of the new hydraulic cement and concrete materials. The performance advantages of these materials will be realized at competitive cost, with robust mix designs that can be tailored towards locally available materials. Sustainability and safety are also among the positive attributes of the new hydraulic cement and concrete materials. Repair of airfield and highway pavements are the immediate applications targeted for the new class of materials. The robust nature of these materials enables their broader infrastructure repair applications. Strong commercial partnerships have been formed to facilitate transition of the end products to the targeted markets.