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981.
The height of 101‐storey Shanghai World Financial Center Tower is 492m above ground making it possible the tallest building in the world when completed. Three parallel structural systems including mega‐frame structure, reinforced concrete and braced steel services core and outrigger trusses, are combined to resist vertical and lateral loads. The building could be classified as a vertically irregular structure due to a number of stiffened and transfer stories in the building. Complexities related to structural system layout are mainly exhibited in the design of services core, mega‐diagonals and outrigger trusses. According to Chinese Code, the height 190 m of the building clearly exceeds the stipulated maximum height of for a composite frame/reinforced concrete core building. The aspect ratio of height to width also exceeds the stipulated limit of 7 for seismic design intensity 7. A 1/50 scaled model is made and tested on shaking table under a series of one and two‐dimensional base excitations with gradually increasing acceleration amplitudes. This paper presents the dynamic characteristics, the seismic responses and the failure mechanism of the structure. The test results demonstrate that the structural system is a good solution to withstand earthquakes. The inter‐storey drift and the overall behaviour meet the requirements of Chinese Design Code. Furthermore, weak positions under seldom‐occurred earthquakes of seismic design intensity 8 are found based on the visible damages on the testing model, and some corresponding suggestions are proposed for the engineering design of the structure under extremely strong earthquake. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
982.
983.
邓敏贞 《资源与生态学报(英文版)》2012,3(2):183-191
建筑是能源消耗大户,也是导致环境污染与气候变化的原因之一.推动绿色建筑的发展,是实现低碳经济与可持续发展的重要路径.当前,中国已经颁布了一些法律法规以及通过信息工具——绿色建筑认证等制度措施来推动绿色建筑的发展,但是实践中存在一些问题,相关制度设计也不够成熟.美国以及欧盟在绿色建筑方面的立法与实践经验相对比较丰富.中国可以借鉴这些国家的一些成功经验,采取一些措施促进绿色建筑的发展,如提高人们对绿色建筑的认识,设计出更多样化的激励工具等等. 相似文献
984.
985.
986.
In this paper, a model able to analyse the seismic behaviour of road network in urban areas, considering interaction between buildings and roads is presented. Damage to buildings and short-term countermeasures, such as propping, can affect roads and even block them, reducing capacity of the road network. Two successive phases are considered. In the first, immediately after the seismic event, emergency services have to reach the relevant buildings. Here, the network topology is of interest. In the second, in the long term, network capacity is not yet completely restored and network demand has to account for displaced people due to unusable buildings. In this case, road serviceability is of interest. In order to consider uncertainties on building behaviour, a probabilistic approach is developed and the network is analysed by means of Monte Carlo simulation. The methodology is applied to the municipality of Potenza (southern Italy) evaluating in the short term, the probability of strategic buildings are not connected and, in the long term, road serviceability. 相似文献
987.
The objective of this work is to obtain estimations of the amplification factors α and δ used for torsion design of buildings, from experiments. For this study, simple one‐storey torsionally unbalanced (TU) steel models were considered. Models consisted of a deck supported on four columns with a selected arrangement of hinges at column ends. Two theoretical structural eccentricities (e = 0.05 and 0.15) were considered. Models were excited with a simple long‐period pendulum consisting of a hanging platform with a forced‐vibration generator on it. Eight models were tested at several excitation levels (frequencies and force magnitudes) in both ranges of behaviour: elastic and inelastic. Experiments were conducted at three frequency ratios of excitation. Registered accelerations of the pendulum platform indicate that the experimental set‐up leads to excitations that resemble narrow‐band seismic ground motions. Frame shear force estimations, based on accelerations recorded at both deck sides, indicate that torsion design factors (α and δ) depend on eccentricity. Estimations of frame shears based on measurements indicate that for normalized eccentricities e ? 0.025, the amplification α can be between 2 and 3; while δ factor resulted between 0.0 and 1.6. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
988.
989.
利用震害期望损失率方法对考虑结构抗力因素的建筑物地震保险纯费率的厘定方法作了分析,并采用该厘定方法得到了两个工程实例的砖结构、钢筋混凝土结构的建筑物地震保险的纯费率. 相似文献
990.