Original Paper(Vol.56 No.8 pp.724-729)

Mechanical Properties of Concrete Used Sewage Sludge Molten Slag as Fine or Coarse Aggregate

Naho TAKEDA and Takayuki KOJIMA

Abstract:The purpose of this study is to develop mechanical properties of concrete using sewage sludge molten slag as fine or coarse aggregate. As sewerage system spreads, sewage sludge that comes out from process of sewerage disposal is increasing. However remaining capacity of final disposal site is almost outer limit, and it is difficult to secure new disposal site. To build the recycling society is important to build sustainable development, and at present 70 percent sewage sludge is recycled. Sewage sludge slag is recycled as construction materials, fertilizer and fuel. The following were clarified by this research. Amount of elusion of heavy metals from sewage sludge molten slag were lower than environmental standards. Strength, durability factor of freezing thawing decreased as the slag substitution ratio increased used sewage sludge slag as coarse aggregate. However, they did not decreased as the slag substitution ratio increased used sewage sludge slag as fine aggregate.

Key Words:Sewage sludge molten slag, Fine aggregate, Coarse aggregate, Mechanical properties, Durability factor of freezing and thawing