Determination of the expansion force of coarse steel slag aggregate

Expansion force and autoclave disruption tests have been developed for measuring the expansion force generated by coarse steel slag aggregate. Equations are deduced to convert the measured expansion force to expansion force of unit volume slag and an individual slag particle. The tension stresses of steel slag particles, 0.64–1.28 MPa, are used to quantitatively evaluate the stability of steel slag and related to the tensile stress of cement mortar matrix. Based on the results and modeling, the inherent relationship between the expansion force of steel slag and the allowable stress of a rigid matrix is revealed. Usability criterion for the use of steel slag under confined conditions can be further developed.