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. © 2007 The Society of Materials Science.
