Abstract
In our country, in connection with economic development, the industrial by-product is discharged so much, those reuse is promoted more than former, and to control waste disposal as much as possible is desired. For example, the ferro-nickel slag (FNS) which is a by-product of nonferrous-metal refinement is reused as fine aggregate, however has not resulted in reuse about fine powder. The fine powder of iron oxide generated as dust-collecting dust is used abundantly as improved material of subgrade soil, but there are several problems which should be made clear. A purpose of this study is to use the materials which mixed lime to FNS and the iron oxide as improvement materials of subgrade soil. As a result, the mixed ratio of between the fine powder and the lime which was expected the strength development clarified by the unconfined compression test. Furthermore, the effect of those improved materials was confirmed by mixing to the decomposed granite.
