Experimental analysis on cyclic performance of concrete columns with TempCore or Dual-Phase steel reinforcement

Structural and economical performance of reinforced concrete frames with Dual‐Phase and TempCore® steel rebars in uncorroded and corroded conditions

“…The design was performed according to EN1998‐1:2005 7 and D.M.17/01/2018 23 following the capacity design approach. The same indications adopted for ordinary RC buildings were followed, even concerning structural details of sections and elements; this choice was the direct consequence of what observed in References 19 and 20 about the reliability of adopting the capacity design rules even for DP grades, achieving the expected performance of RC substructures.…”

“…Twodimensional frame models with lumped plastic hinges were elaborated for each of the two main directions using the OpenSees ® software. 24 The modeling of the nonlinear behavior was limited to those portions where relevant cracks occurred according to the experimental evidence, as discussed in Caprili et al 19,20 keeping elastic all the other parts not involved in plastic deformations. To describe the nonlinear behavior of plastic hinges a specific nonlinear mechanical model was elaborated by the authors, where the main features of the RC section are represented along the plastic hinge length through truss elements, similarly to what performed through a fiber-section approach.…”

“…To describe the nonlinear behavior of plastic hinges a specific nonlinear mechanical model was elaborated by the authors, where the main features of the RC section are represented along the plastic hinge length through truss elements, similarly to what performed through a fiber-section approach. The mechanical model was calibrated in its components using the results of the experimental campaign presented in Caprili et al 19,20 and therefore adopted for different sections of elements. Moment-rotation (M-θ) relationships were then directly derived from the mechanical model without requiring the adoption of consolidated equations valid, perhaps, mainly for ordinary reinforcing steels with defined yielding plateau.…”

“…It was following this idea that during the last years Dual‐Phase (DP) rebars were deeply investigated 15,16 : their typical microstructure, where martensite and ferrite coexist in the same matrix, highly reduces the sensitivity to corrosion phenomena providing, in the meanwhile, adequate strength and deformation capacity. In the framework of the European RFCS project NEWREBAR “New Dual‐Phase steel reinforcing bars for enhancing capacity and durability of anti‐seismic moment resisting frames” (2015–2019), new enhanced typologies of reinforcing bars with DP microstructure were developed, produced, characterized, and applied to constructions, highlighting the improvement given in terms of structural and economic convenience 17–22 . In the present work, the techno‐economic impact of adopting DP grades in RC constructions as alternative to traditional TempCore® is analyzed through the evaluation of the expected annual loss (EAL) index for a typical residential case‐study building, in reference, and corroded conditions.…”

“…In the framework of the European RFCS project NEWREBAR "New Dual-Phase steel reinforcing bars for enhancing capacity and durability of anti-seismic moment resisting frames" (2015-2019), new enhanced typologies of reinforcing bars with DP microstructure were developed, produced, characterized, and applied to constructions, highlighting the improvement given in terms of structural and economic convenience. [17][18][19][20][21][22] In the present work, the techno-economic impact of adopting DP grades in RC constructions as alternative to traditional TempCore ® is analyzed through the evaluation of the expected annual loss (EAL) index for a typical residential case-study building, in reference, and corroded conditions. The aim of the adopted procedure is, besides highlighting the "performance" benefit related to the higher durability of DP rebars, showing that costs connected to the introduction of a new product on the reinforcement market can be justified and sustained if kept below a reasonable threshold.…”