Behavior of Steel Slag used as Sand Alternative in the Marine Environment = Behavior of Steel Slag used as Sand Alternative in the Marine Environment

다국어 초록 (Multilingual Abstract)

Tidal flats and seagrass beds were decreased in Japan by landfilling and others. So in recent years, coast regeneration projects have been progressed in order to recover tidal flats and seagrass beds. A sand-alternative material for creation of land is needed which could have safety, environmental friendly and stable supply, then steel slag meets these requirements. However, steel slag normally doesn't have silt faction and solidification is happen by the elution of Ca and Fe from slag in sea water. In our previous butch experiment, dredged soils obtained from sea sediment has a possibility to supply silt fraction and reduce the solidification. In this paper, we reviled the solidification behavior of steel slag in seawater during 10 months, and the effect of the addition of dredged soil to steel slag and there mechanism. The slag were bonded to each other with iron oxide, and shear stress was 3 times increased in slag only. The addition of dredged soil decrease the shear stress, and also interfere the solidification of slag. ORP or/and embrittlement effect as impurities by the components in dredge soil were the reason of these inhibition of the formation of the bridge between slags by the dredge soil.