Bond Behavior of Steel Rebars in High-Performance Fiber-Reinforced Concretes: Experimental Evidences and Possible Applications for Structural Repairs
Alessandro Pasqualini, Marco Pepe, Felice Marco Liberatore, Carmine Lima, Marco Bressan, Enzo Martinelli
Appears on pages(s):
UHPFRC, Bond behavior, Pull-out test, Tension-stiffening, Structural repair
High-performance fiber-reinforced concrete (HPFRC) is among the most advanced structural materials developed over the last decades with the aim to obtain stronger, tougher, and more durable cementitious composites, also in the view of structural repair of existing structures. Over the last years, research has focused on the behavior of HPFRC for investigating their engineering properties, such as compressive strength, flexural and tensile strength, and the corresponding post-cracking response. In this context, this paper presents the results of wide experimental research aimed at analyzing the bond behavior of steel rebars embedded in a tri-component HPFRC mixture. Specifically, both direct pull-out tests and beam tests were executed with the aim to identify the bond-slip law between the steel rebars and the surrounding matrix. The results show that the bond of steel bars in HPFRC is significantly higher than in ordinary structural concrete. Finally, based on the obtained results, some possible applications are figured out for HPFRC to be coupled with existing members in view of possible strengthening interventions. These applications are presented at the level of conceptual design, as further details still need to be developed, which is the final goal of the collaborative industry-academia partnerships that have run the research reported in the present paper.