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281.
考虑非线性的建筑物地基地震液化简化分析方法 总被引:2,自引:0,他引:2
本文在建筑物地基地震液化总应力简化判别方法的基础上,考虑地基土壤的剪切非线性及饱和砂土Martin非线性孔压增长模型,提出了估计建筑物地基孔压增长的简化分析方法,这一方法可用来判别地基的初始液化问题。 相似文献
282.
This paper investigates the effects of supplemental viscous damping on the seismic response of one‐storey, asymmetric‐plan systems responding in the inelastic range of behaviour. It was found that addition of the supplemental damping reduces not only deformation demand but also ductility and hysteretic energy dissipation demands on lateral load resisting elements during earthquake loading. However, the level of reduction strongly depends on the plan‐wise distribution of supplemental damping. Nearly optimal reduction in demands on the outermost flexible‐side element, an element generally considered to be the most critical element, was realized when damping was distributed unevenly in the system plan such that the damping eccentricity was equal in magnitude but opposite in algebraic sign to the structural eccentricity of the system. These results are similar to those noted previously for linear elastic systems, indicating that supplemental damping is also effective for systems expected to respond in the inelastic range. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
283.
Antonello De Luca Elena Mele Javier Molina Guido Verzeletti Artur V. Pinto 《地震工程与结构动力学》2001,30(8):1125-1145
An experimental test program on a full‐scale model representing a sub‐assemblage of the cloister facade of the Sao Vicente de Fora monastery, retrofitted through base isolation, has been recently carried out at the European Laboratory for Structural Assessment of the Joint Research Centre of the European Commission. In this paper an overview of the laboratory model and the experimental results is provided. In particular, firstly the test model is described, including the geometry and mechanical properties of the masonry specimen and the design of the isolation devices; then the testing method and the sub‐structuring of the isolation system are described and the seismic inputs adopted for the pseudo‐dynamic tests are defined. Finally, the experimental results are discussed and compared to the analogous results obtained on the ‘as is’, fixed‐base sub‐assemblage model. The implications of the test outcomes are emphasized and developments of this research line are presented. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
284.
防震减灾计算机管理系统的结构分析动态化研究 总被引:4,自引:1,他引:3
本文研究了全国大中城市示范区防震减灾计算机管理系统动态化的有关问题,主要是针对未来新建房屋的特点,研究了未来新建砖结构和钢筋混凝土结构的房屋实用震害预测方法,给出了计算分析的简化方法和类比分析方法。这一研究成果不仅有助于实现防震减灾计算机管理系统的分析动态化,而且具有实际推广应用价值。 相似文献
285.
介绍在进行建筑物防雷设计时,如何考虑从接闪、分流、屏蔽、均压、接地和布线这六方面来满足防雷技术要求,使新建建筑物防雷措施在设计阶段就能得到完善。 相似文献
286.
Recent natural hazards have exposed the dire consequence of damage and impact upon the built environment. It appears that one of the biggest challenges to the natural hazard mitigation community is how to improve the performance of older building and infrastructure to enhance their ability to withstand natural hazards. By improving their performance, the risk associated with buildings and infrastructure against natural hazards can be mitigated. Within the context of risk management of buildings against earthquakes, the general practice is to follow a three-step process, namely screening, evaluation and mitigation. Screening constitutes a preliminary evaluation process and sets priority for detailed evaluation. Evaluation compares a built environment with code requirements for new construction and sets priority for mitigation. Mitigation can be achieved by means of retrofit or replacement. Retrofit is intended to improve the performance of built environment as required. Replacement may be the only viable solution when economical, technical and environmental considerations are account for. 相似文献
287.
Angelo Masi 《Bulletin of Earthquake Engineering》2003,1(3):371-395
The seismic vulnerability of some frame structures, typical of existing Reinforced Concrete buildings designed only to vertical
loads, has been evaluated. They are representative of building types widely present in the Italian building stock of the last
30 years. A simulated design of the structures has been made with reference to the codes in force, the available handbooks
and the current practice at the time of construction. The seismic response is calculated through non linear dynamic analyses
with artificial and natural accelerograms. Three main types have been examined: bare frames, regularly infilled frames and
pilotis frames. The results show a high vulnerability for the pilotis buildings: they can be assigned to the class B of the
European Macroseismic Scale of 1998 (EMS98). On the contrary, a low vulnerability (class D of EMS98) can be attributed to
the regularly infilled buildings: in this case collapse can be considered unlikely also with strong earthquakes. An intermediate
seismic behavior is shown by buildings without infills, whose vulnerability can be placed between the classes B and C of EMS98.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
288.
高层建筑动力反应实测中测点的优化布置方法的研究 总被引:3,自引:0,他引:3
本文对高层建筑动力反应实测中测点的优化布置方法进行了研究,研究了几种表示测点布置是否最优的适应度函数,并且应用最优化计算方法来寻找测点最优或接近优化的布置。本文还通过一个高层建筑动态响应测试的实例,说明了具体的应用方法。实际计算表明,用本文方法布置测点所测得的结构动态响应结果有相当高的精度。 相似文献
289.
叠层橡胶隔震支座的动态稳定性和力学特性研究 总被引:2,自引:0,他引:2
文章基于简化分析和动力实验,讨论了在隔震建筑设计中与叠层橡胶支座稳定性相关的问题。指出应考虑多个因素,合理确定隔震支座的设计竖向承载力和水平变位限值。另外,根据实测结果,指出准静力实验和动力实验对支座参数可能得出的不同估计,以及在水平地震输入下,隔震体系将发生竖向牵连振动。 相似文献
290.
Rakesh K. Goel 《地震工程与结构动力学》2005,34(7):825-846
This investigation is concerned with the seismic response of one‐story, one‐way asymmetric linear and non‐linear systems with non‐linear fluid viscous dampers. The seismic responses are computed for a suite of 20 ground motions developed for the SAC studies and the median values examined. Reviewed first is the behaviour of single‐degree‐of‐freedom systems to harmonic and earthquake loading. The presented results for harmonic loading are used to explain a few peculiar trends—such as reduction in deformation and increase in damper force of short‐period systems with increasing damper non‐linearity—for earthquake loading. Subsequently, the seismic responses of linear and non‐linear asymmetric‐plan systems with non‐linear dampers are compared with those having equivalent linear dampers. The presented results are used to investigate the effects of damper non‐linearity and its influence on the effects of plan asymmetry. Finally, the design implications of the presented results are discussed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献