The paper discusses the results of a laboratory study, aimed to evaluate the suitability of electric arc furnace steel slags (EAF), obtained from different Italian plants, to be recycled in the lithic skeleton of bituminous mixtures, for road flexible pavements. The research involved a preliminary evaluation of the chemical, physical and geotechnical properties of the steel slags by itself; it was followed by a mechanical characterization of both traditional and high performances bituminous mixtures (porous asphalt, stone mastic asphalt, high modulus mixes) made with steel slags. The Marshall methodology, integrated by the indirect tensile test, was used to identify the optimum bitumen content of the mixtures. The performance of the asphalt concretes, were checked by means of the stiffness modulus test and the repeated load axial test. Because the requisites for acceptance in the Italian Specifications and Standards have been satisfied (Marshall Stability, Marshal Quotient and Indirect Tensile Strength up to 2170 daN, 778 DaN/mm and 3.2 MPa, respectively, depending on the mixture) and given the positive mechanical performances, it has been verified that the steel slags can be used as partial substitution (up to 51% on the weight of the aggregate) of the lithic materials in the road constructions.
Mechanical properties of asphalt concretes with steel slags
BALDO, Nicola;
2011-01-01
Abstract
The paper discusses the results of a laboratory study, aimed to evaluate the suitability of electric arc furnace steel slags (EAF), obtained from different Italian plants, to be recycled in the lithic skeleton of bituminous mixtures, for road flexible pavements. The research involved a preliminary evaluation of the chemical, physical and geotechnical properties of the steel slags by itself; it was followed by a mechanical characterization of both traditional and high performances bituminous mixtures (porous asphalt, stone mastic asphalt, high modulus mixes) made with steel slags. The Marshall methodology, integrated by the indirect tensile test, was used to identify the optimum bitumen content of the mixtures. The performance of the asphalt concretes, were checked by means of the stiffness modulus test and the repeated load axial test. Because the requisites for acceptance in the Italian Specifications and Standards have been satisfied (Marshall Stability, Marshal Quotient and Indirect Tensile Strength up to 2170 daN, 778 DaN/mm and 3.2 MPa, respectively, depending on the mixture) and given the positive mechanical performances, it has been verified that the steel slags can be used as partial substitution (up to 51% on the weight of the aggregate) of the lithic materials in the road constructions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
