# Design Method of Core-Separated Assembled Buckling Restrained Braces Confined by Two Lightweight Concrete-Infilled Tubes

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## Abstract

**:**

## 1. Introduction

## 2. Composition and Characteristics of CSA-BRB

## 3. Calculation Method of the Restraint Ratio of CSA-BRB

## 4. CSA-BRB Ultimate Bearing Capacity Parasitic Bearing Restraint Ratio Threshold

#### 4.1. Finite Element Model

#### 4.2. Axial Elastic-Plastic Bearing Capacity

#### 4.3. Restraint Ratio Thresholds for Bearing Elements

## 5. Hysteretic Energy Dissipation Performance

#### 5.1. Material Ontology Modeling

#### 5.2. Hysteretic Load System

#### 5.3. Hysteretic Energy Dissipation Performance

#### 5.4. Restraint Ratio Threshold of CSA-BRB Energy-Dissipating Type

## 6. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 8.**Stress distribution and deformation of example CSA-20-1.91 at points A, B, and C in Figure 6a. (

**a**) von Mises stresses and lateral deformations for the initial yield state of the core of the CSA-BRB at point A in Figure 6a. (

**b**) von Mises stresses and lateral deformations for the ultimate state of the core of the CSA-BRB at point B in Figure 6a. (

**c**) von Mises stresses and lateral deformations for the final state of the core of the CSA-BRB at point C in Figure 6a.

**Figure 10.**The material constitutive relationships for steel components in the FE models of CSA-BRBs.

**Figure 12.**Hysteretic curves for numerical examples (No. 1) in Table 3.

No. | b_{c} × t_{c}/mm | P_{y,c}/kN | b_{f} × h_{f} × t_{f}/mm | t_{w}/mm | h_{w}/mm | ζ |
---|---|---|---|---|---|---|

CSA-20-ζ | 240 × 40 | 4512 | 400 × 200 × 10 | 10 | 100~320 | 1.15~3.13 |

CSA-18-ζ | 240 × 30 | 3384 | 360 × 150 × 10 | 10 | 100~320 | 1.04~3.40 |

CSA-15-ζ | 240 × 24 | 2707 | 336 × 120 × 8 | 10 | 120~300 | 1.26~3.64 |

CSA-12-ζ | 240 × 24 | 2707 | 336 × 120 × 8 | 10 | 60~200 | 1.17~3.32 |

No. | P_{y,c}/kN | P/kN | δ/m | ${M}_{e,FM}/kN\xb7m$ | ${M}_{e,0}/kN\xb7m$ | $\alpha $ |
---|---|---|---|---|---|---|

CSA-20-2.68 | 4512 | 6090 | 0.14 | 861 | 506 | 1.70 |

CSA-18-2.60 | 3384 | 4616 | 0.13 | 625 | 356 | 1.76 |

CSA-15-2.75 | 2707 | 3702 | 0.11 | 429 | 239 | 1.80 |

CSA-12-2.75 | 2707 | 3719 | 0.08 | 310 | 177 | 1.75 |

No. | b_{c} × t_{c}/mm | P_{y,c}/kN | b_{f} × h_{f} × t_{w}/mm | h_{w}/mm | ζ | $\phi $ |
---|---|---|---|---|---|---|

CSA-20-ζ | 240 × 40 | 4512 | 400 × 200 × 10 | 200~340 | 1.91~3.37 | 1.03~1.60 |

CSA-18-ζ | 240 × 30 | 3384 | 360 × 150 × 10 | 180~340 | 1.72~3.70 | 1.00~1.60 |

CSA-15-ζ | 240 × 24 | 2707 | 336 × 120 × 8 | 180~310 | 1.87~3.82 | 1.02~1.60 |

CSA-12-ζ | 240 × 24 | 2707 | 336 × 120 × 8 | 110~220 | 1.78~3.74 | 1.00~1.60 |

No. | h_{w} | ζ | φ | Hysteretic Curve |
---|---|---|---|---|

CSA-20-ζ | 200~330 330~340 | 1.91~3.24 3.24~3.36 | 1.03~1.60 1.60 | pinch plump |

CSA-18-ζ | 180~300 300~340 | 1.72~3.12 3.12~3.70 | 1.00~1.60 1.60 | pinch plump |

CSA-15-ζ | 180~280 280~310 | 1.87~3.30 3.30~3.82 | 1.02~1.60 1.60 | pinch plump |

CSA-12-ζ | 110~200 200~220 | 1.78~3.30 3.30~3.74 | 1.00~1.60 1.60 | pinch plump |

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**MDPI and ACS Style**

Zhu, B.; Zhao, J.; Yang, Y. Design Method of Core-Separated Assembled Buckling Restrained Braces Confined by Two Lightweight Concrete-Infilled Tubes. *Appl. Sci.* **2023**, *13*, 4306.
https://doi.org/10.3390/app13074306

**AMA Style**

Zhu B, Zhao J, Yang Y. Design Method of Core-Separated Assembled Buckling Restrained Braces Confined by Two Lightweight Concrete-Infilled Tubes. *Applied Sciences*. 2023; 13(7):4306.
https://doi.org/10.3390/app13074306

**Chicago/Turabian Style**

Zhu, Boli, Junyuan Zhao, and Yuqing Yang. 2023. "Design Method of Core-Separated Assembled Buckling Restrained Braces Confined by Two Lightweight Concrete-Infilled Tubes" *Applied Sciences* 13, no. 7: 4306.
https://doi.org/10.3390/app13074306