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221.
高层隔震建筑设计中隔震支座受拉问题分析   总被引:11,自引:0,他引:11  
高层建筑由于高宽比相对较大,倾覆效应明显,当采用隔震技术时,有可能使隔震支座出现拉应力,而通常使用的叠层橡胶隔震支座抗拉能力不强。因此,隔震支座受拉问题成为隔震技术在高层建筑中推广应用的主要障碍之一。本文提出了避免隔震支座受拉的上部结构布置原则及隔震层优化设计方法,并对目前隔震支座拉应力计算方法提出了改进建议。本文的研究工作可为工程设计提供借鉴,为隔震设计相关规范的修订提供依据。  相似文献   
222.
福建顺昌ML4.7级地震建筑物震害分析   总被引:1,自引:1,他引:1  
介绍了福建顺昌4.7级地震震区建筑物震害的调查结果,归纳了建筑物震害的特征,并对各类建筑物的破坏原因进行了分析。在此基础上,提出灾区重建抗震措施。  相似文献   
223.
地铁列车曲线运行引起学校建筑物振动响应分析   总被引:1,自引:0,他引:1       下载免费PDF全文
地铁以其快捷、准时、运量大等优点,已成为重要的轨道交通形式,但由此引起的环境振动问题日益突出.针对杭州市地铁3号线曲线地段的某中学建设工程,利用有限元软件ABAQUS,对车辆-普通整体道床轨道系统的竖向耦合模型进行振动响应分析,得到考虑轨道高低不平顺影响的轨道振动源强.应用有限元软件MIDAS GTS/NX,建立双孔平...  相似文献   
224.
为保障住户地震安全和进一步研究多层砖房的抗震性能,由企业出资与研究所合作,在三向振动台上进行以四幢砖住宅为一系列的模型试验.本文为其研究论文之一,着重阐述在系列模型的设计中和地震模拟试验中的关键技术以及试验的最终结果.  相似文献   
225.
This paper presents a detailed study on feasibility of un‐bonded fiber reinforced elastomeric isolator (U‐FREI) as an alternative to steel reinforced elastomeric isolator (SREI) for seismic isolation of un‐reinforced masonry buildings. Un‐reinforced masonry buildings are inherently vulnerable under seismic excitation, and U‐FREIs are used for seismic isolation of such buildings in the present study. Shake table testing of a base isolated two storey un‐reinforced masonry building model subjected to four prescribed input excitations is carried out to ascertain its effectiveness in controlling seismic response. To compare the performance of U‐FREI, same building is placed directly on the shake table without isolator, and fixed base (FB) condition is simulated by restraining the base of the building with the shake table. Dynamic response characteristic of base isolated (BI) masonry building subjected to different intensities of input earthquakes is compared with the response of the same building without base isolation system. Acceleration response amplification and peak response values of test model with and without base isolation system are compared for different intensities of table acceleration. Distribution of shear forces and moment along the height of the structure and response time histories indicates significant reduction of dynamic responses of the structure with U‐FREI system. This study clearly demonstrates the improved seismic performance of un‐reinforced masonry building model supported on U‐FREIs under the action of considered ground motions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
226.
基于房屋普查数据的房屋增长规律研究   总被引:1,自引:0,他引:1  
以辽宁省县级以上城镇房屋普查数据、辽宁农村民居房屋普查数据、统计年鉴及抽样调查等房屋数据为基础,对房屋普查数据统计单元进行重新划分及统计计算,实现了房屋普查数据与应急基础数据库房屋数据单元的统一。通过对统计单元各种房屋结构增长率的计算,结合统计分析方法,给出了辽宁省1134个乡镇级统计单元的房屋增长率分类情况。  相似文献   
227.
This paper summarizes the relevant results of the design, construction, testing, and implementation of a nominal 120 kN magnetorheological damper developed to control a free‐plan tall building in Santiago, Chile, equipped with two 160‐ton tuned masses. Cyclic as well as hybrid simulation tests were performed on the prototype damper. Global building responses using measured MR properties showed good correlation with analytical estimations. Also, a proposed physical controller for the MR damper was validated through hybrid and building pull‐back tests. Its performance is essentially equivalent to that of an LQR controller, but the information needed in its implementation is considerably less. Pull‐back tests of 10 cm amplitude were performed on one mass along the flexible edge of the building and its response controlled using the passive and controlled modes of the MR damper. The MR damper was capable of controlling the TM displacements very effectively, as well as the simulated building response for different ground motions and harmonic excitation. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
228.
229.
This paper describes the results of shaking table tests to ascertain the ultimate behavior of slender base‐isolated buildings and proposes a time history response analysis method, which can predict the ultimate behavior of base‐isolated buildings caused by buckling fracture in laminated rubber bearings. In the tests, a base‐isolated structure model weighing 192 kN supported by four lead rubber bearings is used. The experimental parameters are the aspect ratio of height‐to‐distance between the bearings and the shape of and the axial stress on the bearings. The test results indicate that the motion types of the superstructure at large input levels can be classified into three types: the sinking type; the uplift type; and the mixed type. These behaviors depend on the relationship between the static ultimate lateral uplifting force on the superstructure and the lateral restoring characteristics of the base‐isolated story. In the analysis method, bearing characteristics are represented by a macroscopic mechanical model that is expanded by adding an axial spring to an existing model. Nonlinear spring characteristics are used for its rotational, shear, and axial spring. The central difference method is applied to solve the equation of motion. To verify the validity of the method, simulation analysis of the shaking table tests are carried out. The results of the analysis agree well with the test results. The proposed model can express the buckling behavior of bearings in the large deformation range. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
230.
This paper describes the identification of finite dimensional, linear, time‐invariant models of a 4‐story building in the state space representation using multiple data sets of earthquake response. The building, instrumented with 31 accelerometers, is located on the University of California, Irvine campus. Multiple data sets, recorded during the 2005 Yucaipa, 2005 San Clemente, 2008 Chino Hills and 2009 Inglewood earthquakes, are used for identification and validation. Considering the response of the building as the output and the ground motion as the input, the state space models that represent the underlying dynamics of the building in the discrete‐time domain corresponding to each data set are identified. The time‐domain Eigensystem Realization Algorithm with the Observer/Kalman filter identification procedure are adopted in this paper, and the modal parameters of the identified models are consistently determined by constructing stabilization diagrams. The four state space models identified demonstrate that the response of the building is amplitude dependent with the response frequency and damping, being dependent on the magnitude of ground excitation. The practical application of this finding is that the consistency of this building response to future earthquakes can be quickly assessed, within the range of ground excitations considered (0.005g–0.074g), for consistency with prior response—this assessment of consistent response is discussed and demonstrated with reference to the four earthquake events considered in this study. Inclusion of data sets relating to future earthquakes will enable the findings to be extended to a wider range of ground excitation magnitudes. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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