Influence of elevated temperature on properties of radiation shielding concrete with electric arc furnace slag as coarse aggregate

• Published in: Construction & building materials 2020-09, Vol.256
• Main Authors: Beaucour, A.-L., Pliya, Prosper, Faleschini, F., Njinwoua, R., Pellegrino, C., Noumowé, A.
• Format: Article
• Language: English
• Subjects: Civil Engineering; Engineering Sciences
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2020.119385

The development of value-added materials from by-product of the steel-making process can promotesustainability in construction to move towards a circular economy. The use of Electric Arc Furnace(EAF) steel slag as heavyweight coarse aggregate to develop sustainable radiation shielding concretecould provide both technical and economic benefits with less environmental impact. This contributioninvestigates the behaviour at high temperature of a sustainable radiation shielding concrete. Thermalbehaviour of EAF slag concrete was compared to another heavyweight concrete made of barite aggregatesand to a normal-weight concrete. On one hand, the thermal stability of the three different aggregates wasdetermined via simultaneous Thermogravimetry and Differential Scanning Calorimetry analyses andvisual observations after 10 C/min heating. On the other hand, the evolution of thermal conductivityof concretes during heating, the residual mechanical properties and the assessment of potential spallingoccurrence were investigated. Stereo-microscope and Scanning Electron Microscope pictures provideadditional explanations by showing the paste-aggregate interface after heating at 450 C. The results indicatedthat EAF concrete displayed less strength reduction at increasing temperature. This improved behaviouris attributed to both the strong bond between the paste and the aggregates, and the better thermalbehaviour of the EAF slag aggregates compared to barite aggregates.