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Buckling-restrained brace with CFRP encasing: Mechanical behavior & cyclic response

  • Razavi, S. Ali (Faculty of Civil Engineering, University of Tehran) ;
  • Kianmehr, Amirhossein (Faculty of Civil Engineering, University of Tehran) ;
  • Hosseini, Abdollah (Faculty of Civil Engineering, University of Tehran) ;
  • Mirghaderi, S. Rasoul (Faculty of Civil Engineering, University of Tehran)
  • Received : 2016.06.12
  • Accepted : 2018.04.17
  • Published : 2018.06.25

Abstract

Buckling-restrained braces (BRBs) have received considerable attention in seismic design of various types of structures. Conventional BRBs are composed of steel core and surrounding steel tube filled with concrete. Eliminating the steel tube can be advantageous to BRB. In this study the idea of replacing the steel tube by CFRP layers in BRBs is proposed. The advantages of this type of BRB are mentioned, and its design criteria are introduced. The construction procedure of two BRB specimens is described. The specimens are uniaxially tested based on moderate, and severe earthquake levels and the performance of the specimens is investigated. The backbone curves resulted from the hysteresis curve are presented for the design proposes. The results of this study show that CFRP layers can effectively provide the expected performance of the encasing, and the proposed BRB can be considered a viable alternative to the conventional BRBs.

Keywords

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