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Rapid hardening of cement was achieved in the present study by adding a mechanically activated Al(OH) 3 -Ca(OH) 2 mixture to the starting cement paste. Among the dominant parameters for hardening were the mechanical treatment time for the Al(OH) 3 powder and the Al(OH) 3 /Ca(OH) 2 ratio. The hardening mechanisms are discussed here in terms of the ionic concentration of the solution and the hydration products created when the Al(OH) 3 -Ca(OH) 2 mixture was added to water. Mechanical activation of the Al(OH) 3 powder accelerated dissolution into an aqueous alkaline solution and induced the formation of calcium aluminate hydration products. Those hydration products increased the compressive strength of the cement paste at a very early stage of hardening.

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The samples from A-type zeolite and ground soda-lime glass powders were solidifed by calcinations at 600 to 800°C in air atmosphere. These hybrid zeolite/glass samples at 700°C were in part insufficiently densified and hybrid samples were fully densified at 800°C, although the densification was not generated at 600°C. A-zeolites were still stable in glass melt at 800°C for hybrid zeolite/glass samples. These hybrid zeolite/glass samples had the ion exchange ability of 20% against Sr 2+ and the high ability over 80% against Cs + as well as A-zeolite. Microstructures of obtained hybrid zeolite/glass samples were evaluated.