Temperature-Induced Changes in Binders Produced from Concrete Waste: Strength and Rehydration Mechanisms

This study aims to investigate the effect of elevated temperatures simulating fire exposure conditions on the strength and rehydration behavior of binders produced from concrete waste.The concrete waste was ground in a laboratory mill to a specific surface area of approximately 350 m 2 /kg.The binder was burned at 400 and 600.Compression and density tests showed that the mechanical properties were not significantly affected at 600.The microstructure of the samples was analyzed, and the results indicated that the natural behavior of the samples during hydration and aging was identical to that of reference samples.Differential thermal analysis revealed that the mass loss curves during heating exhibit no abrupt transitions except at 133 and 778.Polymorphic changes in C3S and C2S begin at temperatures of 920 and above.Therefore, it was concluded that burning temperatures of 400 and 600 do not affect the mineral components of the binder.To evaluate the hydraulic hardening capacity and deformation behavior of the specimen, the results indicated that the behavior of the specimens was not affected by the firing of the binder at temperatures of 400 and 600.The results of this research revealed valuable insights into the effects of temperature, suggesting the potential use of concrete waste from building demolition exposed to high temperatures as a sustainable basic binder.