State of the art of buckling-restrained braces in Asia

Xie, Qiang

doi:10.1016/j.jcsr.2004.11.005

Cited by 331 publications

(134 citation statements)

References 12 publications

Supporting

Mentioning

125

Contrasting

Unclassified

Order By: Relevance

“…This ultimately allows the brace to attain large inelastic capacities, thus dissipating the seismic energy and allowing the remainder of the structure to remain elastic. This conceptual behavior of conventional and BRB braces, showing the difference in hysteretic behavior is illustrated in Figure 2 (Xie, 2004).…”

Section: Buckling Restrained Bracesmentioning

confidence: 93%

“…Eventually the concept of utilizing a debonding material was effectively applied by a team of investigators in Japan (Watanabe et al 1988;Wada et al 1989;Watanabe and Nakamura 1992) and resulted in the BRB known in Japan as the "Unbonded Brace". These braces are used widely in Japan today and consist of four key parts: the brace to carry axial force, a stiffened transition section between the connection and the brace, a buckling restraining tube to encase the brace and prevent buckling, and a separation phase between the brace and bucklingrestraint filled with a debonding material (Xie, 2004). Figure 2.5 illustrates the components of an unbonded brace.…”

Section: Buckling Restrained Bracesmentioning

confidence: 99%

“…Several options for debonding materials have been proposed including epoxy resin, silicon resin, vinyl tapes and combinations of these. The gap between the brace member and encasing material should also be considered to allow for transverse expansion of the brace (Xie, 2004). It is also important to address local buckling of brace projections.…”

Section: Buckling Restrained Bracesmentioning

confidence: 99%

“…BRBs, enlarging the moment of inertia of the projections of the brace by changing or enlarging the brace cross-section, or adding stiffening plates to the core braces will address this issue (Xie, 2004 detailing. Also, an adjusted brace strength is necessary for member and connection design.…”

Section: Buckling Restrained Bracesmentioning

confidence: 99%

“…Likewise, a low stiffness will not be able to restrain global buckling deformations. Therefore, in design of such systems, it is critical to find a balanced combination of stiffness and strength of the encasing member (Xie, 2004). Black et al (2004) presented computed stiffness values for comparison with measured stiffness values of BRBs.…”

Section: Seismic Performance Of Brbsmentioning

confidence: 99%

See 4 more Smart Citations

Conceptual Investigation of Partially Buckling Restrained Braces

Abraham¹,

Harries²

2007

Structural Engineering Research Frontiers

View full text Add to dashboard Cite

Although in its infancy, leveraging high strength fiber reinforced polymer (FRP) materials for retrofit of steel structures has been the focus of recent investigations. Studies include the application of FRP to steel for flexural and fatigue or fracture retrofit as well as improving steel member stability. The research presented in this thesis attempts to introduce the concept of an FRP-stabilized steel member through a retrofit application creating a Partially Buckling Restrained Brace (PBRB). A PBRB seeks to increase steel brace stability and hysteretic energy dissipation during a seismic event through the strategic application of bonded FRP materials along its length.Six 65 ½" long A992 Gr. 50 WT6x7 steel braces were tested under cyclic compressive loading to failure. Two braces were retrofitted with carbon FRP (CFRP) and two braces were retrofitted with glass FRP (GFRP). One brace was encased in an HSS 7 x 0.125" steel tube and filled with grout to create a conventional Buckling Restrained Brace (BRB). The final brace was an unretrofit control specimen. Two arrangements of FRP materials were used for both the CFRP and GFRP retrofit braces: (1) 2" wide strip was applied to each side of the stem of the WT, and (2) 1" wide strips were applied to each side of the stem in an effort to optimize the retrofit application.The GFRP specimens increased the axial capacity of the brace by 6% and 9%, whereas the CFRP specimens had no effect. The observed variability in axial capacity was largely a result iv of initial loading eccentricities. The GFRP specimens did however show greater control over residual deflections suggesting that the retrofit can delay the formation of a plastic hinge within the brace and maintain compressive capacity through several cyclic loading loops. All of the FRP-retrofit specimens reduced weak-axis lateral displacement of the braces and showed increased control of local behavior. However, the brace is not dominated by local behavior due to its length, and this application may be better suited to shorter braces, similar to those found as cross frames between bridge girders, or to control local buckling in steel I-shaped beams.v

show abstract

Section: Buckling Restrained Bracesmentioning

confidence: 93%

Section: Buckling Restrained Bracesmentioning

confidence: 99%

Section: Buckling Restrained Bracesmentioning

confidence: 99%

Section: Buckling Restrained Bracesmentioning

confidence: 99%

Section: Seismic Performance Of Brbsmentioning

confidence: 99%

See 3 more Smart Citations