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61.
Junxian Zhao Ruobing Chen Yun Zhou Haichao Yu Yuwen Kong Zhan Wang Miaoyuan Dou Yifan Shi 《The Structural Design of Tall and Special Buildings》2019,28(5)
Although buckling restrained braces (BRBs) are commonly applied in seismic buildings to mitigate structural damage, their performance was often limited by rupture of the corner gusset connections due to additional frame action. This issue may be resolved by alternative gusset connections to mitigate the frame–gusset interaction. In this study, commonly used procedures for design of the traditional gusset connection are reviewed, followed by a case study on the effect of frame action on the structural behavior of these gusset connections in steel frames with BRBs. Inspired by these analysis, two different strategies, aiming at releasing frame–gusset shear interaction using sliding gusset connection or reducing normal interaction using dual gusset plates, are tried to mitigate the frame action effects. Finite element analysis is conducted on steel frame subassemblages with/without BRBs to examine the effect of different gusset connections on the structural behavior of these framing systems. It shows that the sliding gusset connection shows beneficial effect in reducing the frame action, having much smaller stress responses on the gusset interfaces, as well as smaller shear force and plastic responses on the framing system. Thus, it becomes a promising gusset connection for improved seismic performance of the steel framing system with brace‐type dampers. 相似文献
62.
Wood‐frame buildings (WFBs) are the most commonly used structural systems for residential applications in North America. Past researches have shown that WFBs are susceptible to soft‐story mechanisms. In this study, a simple, efficient, and economical retrofit strategy, which utilizes continuous pinned‐supported rigid spine columns (RSCs) over the height of the building, is proposed. The retrofit aims to provide uniform deformation through the height of the building to prevent soft‐story mechanisms. This retrofit strategy was applied to a six‐story WFB located in Vancouver, British Columbia, Canada. A three‐dimensional nonlinear finite element model of the prototype building was developed using OpenSees. A comprehensive parametric study was conducted to identify the most economical RSC design. Seismic performance of the prototype building, with and without the most economical RSC design, was assessed through extensive nonlinear time history analyses. Results showed that the proposed retrofit strategy can effectively improve the seismic behavior of WFBs to prevent soft‐story mechanisms. 相似文献
63.
In this paper, the effect of horizontal bracing on enhancing the resistance of steel moment frames against progressive collapse is investigated. Previously designed 6 bay by 3 bay 18‐story steel frame prototype building with 6 m bay span (namely, unbraced frame), which was susceptible to progressive collapse, is retrofitted by four types of horizontal bracing systems on the perimeter of the topmost story and analyzed using 3D nonlinear dynamic method. Six different cross‐sections for each bracing system type are considered, and the capacity curves for each model are obtained. Three column removal circumstances, namely, Edge Short Column, First Edge Long Column, and Edge Long Column are considered in this paper. The results imply that horizontal bracing would increase the resistance of moment frames against progressive collapse. However, one of the bracing types in which axial compressive force is created in braces is not appropriate for retrofitting. 相似文献
64.
Yadong Li Youliang Ding Fangfang Geng Libin Wang 《The Structural Design of Tall and Special Buildings》2019,28(8)
With the rapid development of cities and the invasion of major natural disasters such as earthquakes, the resilience city as a new design concept has been paid more and more attention. As an important branch of self‐centering seismic resisting system, self‐centering concrete frame system has been studied by many scholars. These studies prove that self‐centering concrete frame structure has excellent self‐centering ability but poor energy dissipation capacity. Adhering to the working principle of self‐centering structure and considering the development concepts of building industrialization and modularization, this paper proposed a kind of self‐centering precast concrete frame with hysteretic damper (SCPCHD). In order to verify its energy dissipation capacity and seismic performance, elaborate finite element models were established and elastoplastic dynamic time history analyses were carried out. The results showed that the SCPCHD frame has a similar interstory displacement response to the reinforced concrete (RC) frame and the energy dissipation performance of its joint is obviously superior to the RC frame under rare earthquake because the SCPCHD frame has low damage characteristics and excellent damping device. In summary, this paper proves the feasibility and superiority of the SCPCHD frame, providing reliable support for further research. 相似文献
65.
多层现浇预应力砼框架张拉方案的优化分析 总被引:2,自引:0,他引:2
讨论了四种可行的多层现浇预应力砼框架的张拉方案,计算了不同张拉方案对框架结构综合弯矩的影响,计算表明:不同张拉方案对梁的综合弯矩的影响很小,对柱的影响显著;根据柱弯矩最小的原则,对四种张拉方案进行了优化分析. 相似文献
66.
采用遗传算法对钢框架结构进行了抗震优化设计,编制了分析程序,并分析了算例,证明将遗传算法运用于抗震优化设计是行之有效的,丰富了钢结构优化设计的理论和方法。 相似文献
67.
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69.
马啸溪嘉陵江大桥的施工控制 总被引:1,自引:0,他引:1
马啸溪嘉陵江大桥为预应力连续刚构桥,采用悬臂浇筑施工法进行施工。由于施工过程复杂,结构的内力变化较大,必须对其进行施工过程的控制。本文作者介绍了施工控制的主要原理和方法,并给出了部分测试纵向有效预应力的测试结果。通过有效地施工控制,保证了桥梁建成后的线形和内力符合设计的要求。 相似文献
70.
介绍了规则链武结构的局部模态特性,分析了框架结构的高阶模态及局部模态试验,表明框架结构高阶局部模态具有模态密集特性,子结构和整体结构之间存在着动力耦合。 相似文献