NEUTRAL HARDENING MATERIAL FOR WATERY SOIL, AND SUPPRESSING METHOD FOR HEAVY METAL ELUTION FROM SOIL AND TREATING METHOD FOR DEHYDRATION OF SOIL USING IT

PROBLEM TO BE SOLVED: To provide such a neutral hardening material used in a hardening treatment by means of a hardening material for a watery soil as is neutral and excellent in a hardened strength and to provide an improved method for hardening a watery soil using this hardening material. SOLUTION: The composition comprises 85-99 % by mass of a hydraulic alumina and 1-15 % by mass of lithium carbonate, preferably comprises 65-98 % by mass of a hydraulic alumina, 1-15 % by mass of lithium carbonate and 1-15 % by mass of calcium carbonate, and the composition gives an improved soil with such a high strength in the neutral region as equal to a cement-based hardening material. The method for preventing the elution of heavy metals is characterized by adding and mixing this hardening material of 50-350 kg relative to 1 m3of the object soil. Additionally, the method for dehydrating and hardening a watery soil comprises the steps of adding and mixing the above hardening material of 50-200 kg relative to 1 ton of a dry soil to a highly watery soil with a high water-content of more than 100 % and then dehydrating by means of a dehydrator to thereby give a cake and harden the soil. COPYRIGHT: (C)2005,JPO&NCIPI