Novel High Temperature Geopolymer for Spall-resistant Pavement Materials

During the past couple of decades, there has been considerable interest and research in inorganic polymers (“geopolymers”) for high temperature and for rapid-setting concrete materials. Geopolymers are manufactured by combining aluminosilicates powders with highly alkaline water through polycondensation. The resulting cured geopolymer exhibits high compressive strengths after only four hours of set time. Since geopolymers have no chemically-bound water that can vaporize and cause spalling, the inorganic polymers can be stable up to 1200oC. The mechanical properties of inorganic polymers can be improved significantly if the water content is minimized during mixing, while maintaining good workability of the cement. The proposed optimization technology, along with the use of superplasticizers, will allow the fabrication of low-viscosity geopolymeric pavement materials that will cure to higher densities and compressive strengths and show excellent spall resistance at high temperatures.