Abstract: A cementitious composition which when mixed with water is capable of setting rapidly into a hard mass of high compressive strength without substantial shrinkage during setting and early hardening, which exhibits reduced long-term shrinkage, and which possesses a high degree of impermeability to liquid and vapor, is composed of a particulate mixture of portland cement, a calcined gypsum, and high alumina cement. Alternatively, such a cementitious composition can be composed of a particulate mixture of a high alumina cement and pressure calcined gypsum. Additional components such as surface active agents, gas generating or releasing agents and aggregate can be employed, if desired, for the selective improvement of specific properties.

Abstract: The shrinkage of organic plastics, such as polyepoxies and polyesters, can be controlled by incorporating therein an admixture of solid particulate gas carriers, such as fluid coke, activated alumina, activated bauxite, silica gel, and delayed coke.