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Wang Yayong 《地震工程与工程振动(英文版)》2008,7(3):255-262
Many different types of buildings were severely damaged or collapsed during the May 12, 2008 Great Wenchuan Earthquake. Based on survey data collected in regions that were subjected to moderate to severe earthquake intensities, a comparison between the observed building damage, and the three earthquake performance objectives and seismic conceptual design principles specified by the national "Code for Seismic Design of Buildings GB50011-2001," was carried out. Actual damage and predicted damage for a given earthquake level for different types of structures is compared. Discussions on seismic conceptual design principles, with respect to multiple defense lines, strong column-weak beam, link beam of shear walls, ductility detailing of masonry structures, exits and staircases, and nonstructural elements, etc. are carried out. Suggestions for improving the seismic design of structures are also proposed. It is concluded that the seismic performance objectives for three earthquake levels, i.e., "no failure under minor earthquake level, ""repairable damage under moderate earthquake level" and "no collapse under major earthquake level" can be achieved if seismic design principles are carried out by strictly following the code requirements and ensuring construction quality. 相似文献
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2020年6月交通运输部发布了新版《公路桥梁抗震设计规范》(JTG/T 2231-01-2020)(简称"《公规》")。本文比较了现行《铁路工程抗震设计规范》(GB 50111-2006)(2009年版)(以下简称"《铁规》")与《公规》的抗震设计相关内容,并分别采用两本规范对25m墩高(D类)、35m墩高(C类)和40m墩高(B类)简支梁进行抗震设计,比较二者地震力和配筋设计结果差异。结果表明:《公规》和《铁规》的抗震设计框架和内容基本一致,在具体规定上如E2或罕遇地震设计最大加速度响应值以及桥墩强度和延性验算方法等方面不同;D类桥梁《铁规》地震力明显大于《公规》,C类和B类桥梁《铁规》和《公规》地震力相当;地震力相同时,《铁规》配筋率计算值大于《公规》,因《铁规》配筋设计基于容许应力法,而《公规》基于极限状态法。 相似文献
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详细论述了结构分灾抗震设计的产生背景、设计思想、优化模型和基本原则,指出结构分灾设计是在分析基于投资—效益准则的结构抗震设计模型的基础上,对工程实践中一些成功经验的提炼和概括而形成的设计方法,工程领域中一些现行设计方法和措施就是分灾设计的具体应用。当工程师们待处理的问题必须考虑高度不确定性因素时,将分灾设计作为一种可能选用的设计理念,将有助于工程师们实现设计创新。分灾设计符合基于性能的抗震设计思想,可以方便地实现基于性能的设计。 相似文献
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抗震规范应用强度折减系数的现状及分析 总被引:4,自引:1,他引:4
世界上大多数的抗震规范都采用了基于强度的设计方法,强度折减系数是基于强度的抗震设计中确定设计地震力的关键因素,提高强度折减系数的可靠性已经被认为是提高现有抗震规范可靠性的有效途径。本文主要介绍了抗震研究处于世界先进水平的美国(UBC97)、欧洲(EC8)、日本、墨西哥、加拿大、中国等国家抗震规范中强度折减系数取值的有关规定,然后给出了各国学者关于规范规定的强度折减系数的一些重要讨论和分析,最后指出了世界各国应用强度折减系数过程中存在的不足,指出了需进一步研究的问题。 相似文献
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结构抗震设计中的强度折减系数研究 总被引:27,自引:12,他引:27
借助于单自由度弹塑性动力时程分析程序,对延性结构的强度折减系数进行了研究,在统计平均和回归分析的基础上,建立了平均强度折系数的函数形式,本文所建立的平强度折减系数函数,从理论上明确了结构具有延性对弹性地震力的折减关系,研究成果可供结构抗震设计规范采纳应用。 相似文献
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Regional variation of spectral parameters for seismic design from broadband probabilistic seismic hazard analysis 下载免费PDF全文
The characterisation of the seismic hazard input is a critical element of any seismic design code, not only in terms of the absolute levels of ground motion considered but also of the shape of the design spectrum. In the case of Europe, future revisions of the seismic design provisions, both at a national and a pan‐European level, may implement considerable modifications to the existing provisions in light of recent seismic hazard models, such as the 2013 European Seismic Hazard Model. Constraint of the shape of the long‐period design spectrum from seismic hazard estimates on such a scale has not been possible, however, owing to the limited spectral period range of existing ground motion models. Building upon recent developments in ground motion modelling, the 2013 European Seismic Hazard Model is adapted here with a new ground motion logic tree to provide a broadband Probabilistic Seismic Hazard Analysis for rock sites across a spectral period range from 0.05 seconds to 10.0 seconds. The resulting uniform hazard spectra (UHS) are compared against existing results for European and broadband Probabilistic Seismic Hazard Analysis and against a proposed formulation of a generalised design spectrum in which controlling parameters can be optimised to best fit the uniform hazard spectra in order to demonstrate their variability on a European scale. Significant variations in the controlling parameters of the design spectrum are seen both across and within stable and active regions. These trends can help guide recalibrations of the code spectra in future revisions to seismic design codes, particularly for the longer‐period displacement spectrum. 相似文献
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For the first time after the finalisation of the European Norm for seismic design of buildings (Eurocode 8 – EC8),the performance of RC buildings designed with this code is evaluated through systematic nonlinear analyses. Regular 4-, 8- or 12-storey RC frames are designed for a PGA of 0.2 or 0.4 g and to one of the three alternative ductility classes in EC8. As the Eurocodes are meant to replace soon existing national codes, design and performance is also compared to that of similar frames designed with the 2000 Greek national codes. The performance of alternative designs under the life-safety (475 years) and the damage limitation (95 years) earthquakes is evaluated through nonlinear seismic response analyses. The large difference in material quantities and detailing of the alternative designs does not translate into large differences in performance. Design for either Ductility Class High (H) or Medium (M) of EC8 is much more cost-effective than design for Ductility Class Low (L), even in moderate seismicity. It is also much more cost-effective than design to the 2000 Greek national codes. 相似文献
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Performance assessment implies that the structural, non‐structural, and content systems are given and that decision variables, DVs, (e.g. expected annual loss, mean annual frequency of collapse) are computed and compared to specified performance targets. Performance‐based design (PBD) is different by virtue of the fact that the building and its components and systems first have to be created. Good designs are based on concepts that incorporate performance targets up front in the conceptual design process, so that subsequent performance assessment becomes more of a verification process of an efficient design rather than a design improvement process that may require radical changes of the initial design concept. In short, the design approach could consist of (a) specifying performance targets (e.g. tolerable probability of collapse, acceptable dollar losses) and associated seismic hazards, and (b) deriving engineering parameters for system selection, or perhaps better, using the relatively simple design decision support tools discussed in this paper. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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从欧洲抗震设计规范的一般规定浅谈结构抗震概念设计的重要性 总被引:1,自引:0,他引:1
由于地震的作用以及在这种作用下的结构与构件的受力状况的复杂性和不确定性,结构抗震设计的计算假定与实际情况存在各种差异,甚至有时还根本无法计算.因此在这种情况下,为确保抗震结构性能,就不得不依赖结构抗震的概念设计.结构抗震概念设计是指工程师们根据结构地震破坏的形态和长期积累的实际工程经验等总结形成的符合工程师专业知识的基... 相似文献
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中日规范中关于液化和侧向扩流场地桥梁桩基抗震设计考虑之比较 总被引:1,自引:0,他引:1
评述了我国液化场地和侧向扩流场地桥梁桩基抗震设计规范。总结了中日两国液化场地和侧向扩流场地桥梁桩基的抗震设计方法与技术细节,阐述了日本规范中液化场地和侧向扩流场地桥梁桩基抗震设计中的液化地基土反力折减系数的确定方法,以及土体液化侧向扩流对桩作用力的计算模式。指出我国规范中在液化和侧向扩流场地桩的抗震分析方法、不同土层分界处桩的抗震措施、桩的竖向承载力及桩的屈曲稳定性分析等方面存在的主要问题,据此给出了亟待改进的初步建议。这对我国桥梁工程的抗震安全性具有重要意义,可供我国工程技术人员参考借鉴。 相似文献
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桥梁抗震设计规范的现状与发展趋势 总被引:12,自引:3,他引:9
本文对世界主要桥梁结构抗震设计规范的现状进行了较为详细的对比,指出我国现行《公路工程抗震设计规范》中存在的一些缺点。本文还对目前国际上桥梁结构抗震设计规范的发展动向进行了总结,提出了修订我国新《城市桥梁抗震设计规范》的一些意见。 相似文献
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The paper focuses on the seismic response of walls in dual (frame + wall) structures, with particular emphasis on shear behaviour.
Although dual structures are widely used in earthquake-resistant medium-rise and high-rise buildings, the provisions of modern
seismic codes regarding design of walls for shear are not fully satisfactory, particularly in the (common) case that walls
of substantially different length form part of the same structure. Relevant provisions of the leading seismic codes are first
summarised and their limitations discussed. Then an extensive parametric study is presented, involving two multistorey dual
systems, one with identical walls, and one with walls with unequal length, designed to the provisions of Eurocode 8 for two
different ductility classes (H and M). The walls of the same structures are also designed to other methods such as those used
in New Zealand and Greece. The resulting different designs are then assessed by subjecting the structures to a suite of strong
ground motions, carrying out inelastic time history analysis, and comparing the results against design action effects. It
is found that although modern code procedures generally lead to satisfactory performance (differences among them do exist),
the design of walls seems to be less appropriate in the case of unequal length walls. For this case a modified procedure is
proposed, consisting of an additional factor to account for the relative contribution of walls of the same length to the total
base and an improved envelope of wall shears along the height; this improved method seems to work better than the other procedures
evaluated herein, but further calibration is clearly required. 相似文献
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IntroductionAt present, the proper design and construction of buildings for earthquake-resistance is the most effective measure to mitigate the earthquake damage. In a broad sense, the earthquake resistance design should include the following seven contents:1) Determining the seismic design criteria Determining the seismic design goals3) Determining the seismic design parameters (intensity or ground motion) and their numerical values4) Determining the category of importance for buildings and … 相似文献