INFLUENCE OF RECONSTRUCTION SLAG ON THE PROPERTIES OF CEMENT-BASED MATERIALS

Lei Zhang，Yanan Zhang，Fangfang Wu，Ruihua Liang

ABSTRACT: Melting the mixture of municipal solid waste incineration (MSWI ) fly ash and slag with mass ratio 3: 7 at 1400℃ for 60min ,and then obtained reconstruction slag by air cooling. The effect of reconstruction slag with the dosages of 10%, 30%, 50% on the properties of cement-based materials were studied, and the activity of reconstruction slag and raw slag was also contrasted. Furthermore, the influence mechanism of reconstruction slag on the properties of cement-based materials was analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD). It turned out that the compressive strength showed a trend of decrease after the first increase of the specimen with the increased of reconstruction slag, the compressive strength reach to 45.0 MPa at curing 28 d with the dosage of 30%. The activity of reconstruction slag was higher than the raw slag. Microscopic analysis showed that reconstruction slag contains a certain amount of gehlenite crystals, under alkaline environment, second hydration occur to reconstruction slag, and it generate large numbers of hydration products to make a high strength.

Keywords: cement-based materials, MSWI fly ash, reconstruction slag, properties