• Title/Summary/Keyword: Design centering

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Hysteretic behavior studies of self-centering energy dissipation bracing system

  • Xu, Longhe;Fan, Xiaowei;Lu, Dengcheng;Li, Zhongxian
    • Steel and Composite Structures
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    • v.20 no.6
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    • pp.1205-1219
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    • 2016
  • This paper presents a new type of pre-pressed spring self-centering energy dissipation (PS-SCED) bracing system that combines friction mechanisms between the inner and outer tube members to provide the energy dissipation with the pre-pressed combination disc springs installed on both ends of the brace to provide the self-centering capability. The mechanics and the equations governing the design and hysteretic responses of the bracing system are outlined, and a series of validation tests of components comprising the self-centering mechanism of combination disc springs, the friction energy dissipation mechanism, and a large scale PS-SCED bracing specimen were conducted due to the low cyclic reversed loadings. Experimental results demonstrate that the proposed bracing system performs as predicted by the equations governing its mechanical behaviors, which exhibits a stable and repeatable flag-shaped hysteretic response with excellent self-centering capability and appreciable energy dissipation, and large ultimate bearing and deformation capacities. Results also show that almost no residual deformation occurs when the friction force is less than the initial pre-pressed force of disc springs.

A review on BRB and SC-BRB members in building structures

  • Haider, Syed Muhammad Bilal;Lee, Dongkeun
    • Structural Engineering and Mechanics
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    • v.80 no.5
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    • pp.609-623
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    • 2021
  • Buckling restrained bracing (BRB) was firstly introduced in Japan construction industry in year 1989. With time, BRB performance has been advanced to self-centering BRB (SC-BRB) which has exceptional energy dissipation, addressing the improvement in the structure performance in post-seismic affect. Although the BRB performance specifications are defined in design codes of several countries, specific design provisions are not generally provided since BRBs are usually considered a manufactured device. Furthermore, most of review papers focused on BRB rather than SC-BRB. Thus, this paper explores the background of both BRB and SC-BRB. The importance of self-centering components in BRB and literature related to it have been studied. This review study also highlights the significance of corrosion-resistance materials in the configuring BRB and SC-BRB since most of such members are made of carbon steel that is susceptible to corrosion.

Seismic performance evaluation of steel moment frames with self-centering energy-dissipating coupled wall panels

  • Lu Sui;Hanheng Wu;Menglong Tao;Zhichao Jia;Tianhua Zhou
    • Steel and Composite Structures
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    • v.47 no.5
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    • pp.663-677
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    • 2023
  • The self-centering energy-dissipating coupled wall panels (SECWs) possess a dual capacity of resiliency and energy dissipation. Used in steel frames, the SECWs can localize the damage of structures and reduce residual drifts. Based on OpenSEES, the nonlinear models were established and validated by experimental results. The seismic design procedure of steel frame with SECW structures (SF-SECW) was proposed in accordance with four-level seismic fortification objectives. Nonlinear time-history response analyses were carried out to validate the reasonability of seismic design procedure for 6-story and 12-story structures. Results show that the inter-story drifts of designed structures are less than drift limits. According to incremental dynamic analyses (IDA), the fragility curves of mentioned-above structure models under different limit states were obtained. The results indicate that designed structures have good seismic performance and meet the seismic fortification objectives.

Seismic Response of Self-Centering Energy Dissipative Braced Frames (셀프센터링 가새골조의 지진응답)

  • Choi, Hyun-Hoon;Christopoulos, C.;Kim, Jin-Koo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.331-336
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    • 2008
  • An self-centering energy-dissipative (SCED) bracing system has recently been developed as a new seismic force resistant bracing system. The advantage of the SCED brace system is that, unlike other comparable advanced bracing systems that dissipate energy, such as the buckling restrained brace system, it has a self-centering capability that reduces or eliminates residual building deformations after major seismic events. In this study seismic performance of SCED braced frames is evaluated for a set of 20 design level earthquake records. According to analysis results the SCED systems showed more uniform interstory drift demand for buildings with 8 story or fewer. The residual deformation in SCED buildings turned out to be much less than that of moment-resisting frames.

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Seismic behavior and design method of socket self-centering bridge pier with hybrid energy dissipation system

  • Guo, Mengqiang;Men, Jinjie;Fan, Dongxin;Shen, Yanli
    • Earthquakes and Structures
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    • v.23 no.3
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    • pp.271-282
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    • 2022
  • Seismic resisting self-centering bridge piers with high energy dissipation and negligible residual displacement after an earthquake event are focus topics of current structural engineering. The energy dissipation components of typical bridge piers are often relatively single; and exhibit a certain level of damage under earthquakes, leading to large residual displacements and low cumulative energy dissipation. In this paper, a novel socket self-centering bridge pier with a hybrid energy dissipation system is proposed. The seismic resilience of bridge piers can be improved through the rational design of annular grooves and rubber cushions. The seismic response was evaluated through the finite element method. The effects of rubber cushion thickness, annular groove depth, axial compression ratio, and lateral strength contribution ratio of rubber cushion on the seismic behavior of bridge piers are systematically studied. The results show that the annular groove depth has the greatest influence on the seismic performance of the bridge pier. Especially, the lateral strength contribution ratio of the rubber cushion mainly depends on the depth of the annular groove. The axial compression ratio has a significant effect on the ultimate bearing capacity. Finally, the seismic design method is proposed according to the influence of the above research parameters on the seismic performance of bridge piers, and the method is validated by an example. It is suggested that the range of lateral strength contribution ratio of rubber cushion is 0.028 ~ 0.053.

Finite Element Analysis of the Effect of Centering Groove on Tip Test (센터링 홈이 팁 시험법에 미치는 영향에 대한 유한요소해석)

  • Kang, Seong-Hoon;Im, Yong-Taek
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.7
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    • pp.1340-1347
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    • 2002
  • Finite element simulations are being widely used to increase the efficiency and effectiveness of design of bulk metal forming processes. In such simulations, proper consideration of friction condition is crucial in obtaining reliable results. For this purpose, tip test based on backward extrusion was proposed recently. In this lest, a cylindrical billet is positioned in a shallow groove of a counter punch for centering purpose and formation of a radial tip is induced on the extruded end of the workpiece. In this study, the effect of centering groove on tip test was investigated. The quantitative ratio of the shear friction factors between the punch and die was numerically determined depending on the shape of centering groove. Also, surface expansion and pressure distribution along the punch and die were considered in order to better understand the reason that friction condition at the punch compared to the one of die was more severe.

Vibration suppression in high-speed trains with negative stiffness dampers

  • Shi, Xiang;Zhu, Songye;Ni, Yi-qing;Li, Jianchun
    • Smart Structures and Systems
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    • v.21 no.5
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    • pp.653-668
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    • 2018
  • This work proposes and investigates re-centering negative stiffness dampers (NSDs) for vibration suppression in high-speed trains. The merit of the negative stiffness feature is demonstrated by active controllers on a high-speed train. This merit inspires the replacement of active controllers with re-centering NSDs, which are more reliable and robust than active controllers. The proposed damper design consists of a passive magnetic negative stiffness spring and a semi-active positioning shaft for re-centering function. The former produces negative stiffness control forces, and the latter prevents the amplification of quasi-static spring deflection. Numerical investigations verify that the proposed re-centering NSD can improve ride comfort significantly without amplifying spring deflection.