Title: Use of Slag in Cementitious Matrices for Sprayed Concrete Applications
Author(s): Renan P. Salvador, Dimas A. S. Rambo, Roberto M. Bueno, Kaio T. Silva, and Antonio D. de Figueiredo
Publication: Symposium Paper
Appears on pages(s): 575-589
Keywords: Accelerator, blast-furnace slag, hydration, mechanical properties, sprayed concrete
The use of additions to replace cement in sprayed concrete applications is crucial in order to obtain matrices with proper mechanical properties and durability. Blast-furnace slag is not commonly employed to produce sprayed concrete because of its low reactivity. In this context, the objective of this study is to evaluate the chemical and mechanical properties of sprayed concrete produced with cement and blast-furnace slag as a partial cement replacement. Hydration kinetics were characterized by isothermal calorimetry, while mechanical properties were evaluated by needle penetration resistance and compressive strength of extracted cores. Results showed that slag was activated by accelerators and the resulting matrix fulfilled the requirements of the strength class J 2 . Therefore, blast-furnace slag may be used in sprayed concrete when the average strength class is specified.