共查询到19条相似文献，搜索用时 312 毫秒
1.
大震下被动与智能隔震结构动力可靠度的对比 总被引：9，自引：0，他引：9
对被动及智能隔震结构在“大震”条件下的动力可靠度进行探讨。将被动及智能隔震体系均取作弹塑性模型,并用退化Bouc-W en滞变模型描述上部结构的恢复力,用非退化Bouc-W en模型描述隔震层的恢复力。采用虚拟激励法计算结构的随机响应,根据我国抗震规范中“大震不倒”的设防目标,采用各层最大层间位移峰值响应和累积滞变耗能构造双参数的随机疲劳累积损伤指数,作为功能状态指标。假定各层失效相关,用串联系统计算体系动力可靠度。通过数值算例,对比了被动隔震、智能隔震与非隔震体系的条件失效概率,从动力可靠度角度显示了智能隔震体系的减震优势。 相似文献
2.
3.
《华南地震》2016,(4)
层间隔震结构是基础隔震结构的发展与延伸,作为一种复杂结构体系,基础隔震结构的工作机理不一定完全适合,延长结构的周期可能无法同时降低上、下部结构的地震响应。此类体系以往的理论及试验研究,隔震层的阻尼多由铅芯橡胶支座提供,采用天然橡胶支座及黏滞阻尼器作为隔震层,进行了层间隔震结构振动台试验研究。设计了一个4层的钢框架模型,依次进行了基础固接、基础隔震、1层顶隔震、2层顶隔震及3层顶隔震的振动台试验研究,测定结构的加速度、层间位移及层剪力系数。试验结果表明:黏滞阻尼器层间隔震结构具有良好的减震效果。建立了层间隔震结构的有限元模型,将有限元分析结果与试验结果进行了对比。 相似文献
4.
基于动力可靠度的隔震结构参数模糊优化 总被引：1，自引：0，他引：1
分别选取Bouc—Wen和退化Bouc—Wen模型描述隔震层及上部结构滞变回复力，采用虚拟激励法进行隔震结构随机响应分析。用各层最大层间位移响应和累计疲劳损伤指数建立双参数的功能状态方程，用一次二阶矩理论计算隔震结构失效概率。选用一个隔震框架作为数值算例，探讨了低频过滤器、隔震阻尼比和隔震刚度对隔震结构各子系统条件失效概率的影响。建立了隔震结构参数多目标优化模型，用失效概率确定单因素评判的隶属度，并采用最大隶属度法对隔震参数进行模糊优化。 相似文献
5.
隔震结构"小震不坏"的动力可靠度分析 总被引：7，自引：2，他引：5
本文探讨叠层橡胶隔震体系在“小震不坏”条件下的动力可靠度分析。基于等效线性化的隔震工程设计参数,建立非比例阻尼隔震结构模型。采用双过滤白噪声功率谱模型描述地震动,并用林家浩虚拟激励法进行随机响应分析。以各层的最大层间位移响应作为控制指标,取结构的弹性位移限值作为位移极限值,建立功能状态方程。根据一次二阶矩方法,用串联模式计算体系的总体可靠度。文末选用了一个7层隔震框架作为数值算例,探讨了隔震阻尼、寒冷环境、节点构造误差所引起的隔震层刚度上升,以及场地土类别等对体系动力可靠性的影响。 相似文献
6.
为了研究不同设计参数条件下基础隔震结构非线性响应的概率密度演化特征，采用两质点模型来模拟基础隔震结构，隔震层与上部结构分别采用Bouc-Wen模型与刚度退化的Bouc-Wen模型来描述其非线性特征，运用概率密度演化理论，进行隔震结构非线性随机地震响应的概率密度演化分析。采用基于物理的随机地震动模型生成人工地震动，提出基础隔震结构非线性随机地震响应的概率密度演化分析的基本步骤。通过改变基础隔震结构的设计参数，同时考虑激励的随机性，研究基础隔震结构非线性随机地震响应的概率密度演化规律。结果表明，基础隔震结构的阻尼比、周期比和屈重比取合理范围，能使隔震结构上部和下部的位移可控。 相似文献
7.
基础隔震房屋模型振动台试验研究 总被引：5，自引：0，他引：5
本文结合日本在建的基础隔震实际工程,采用中国有关工厂生产的铅芯橡胶支座的作为基础隔震支座,进行了基础隔震房屋模型和基础固家房屋模型模拟地震动台试验,并引入能量分析方法对两种试验结果进行了分析比较。结果表明,基础隔震模型隔震效果明显,隔震层滞回变能有效吸收地震动入能量,减小模型结构的塑性变形和累积损伤。 相似文献
8.
基础隔震单层偏心结构扭转地震反应分析 总被引：1，自引：0，他引：1
采用微分型滞回恢复力模型模拟隔震支座的恢复力特性，对基础隔震单层偏心结构的扭转地震反应进行分析，研究隔震系统偏心距和上部结构偏心距对结构扭转反应的影响。结果表明，采用隔震技术可以显著降低隔震结构的扭转地震反应。 相似文献
9.
建立在地震作用下设置阻尼器的基础隔震结构在最大地震响应时刻的能量平衡方程,给出了结构隔震支座和阻尼器的能量表达式,演算了基于能量平衡的设置阻尼器的基础隔震结构的地震响应预测式.选用人工地震波和天然地震波,利用时程分析法的解析值验证了地震响应预测式的精度,比较研究了仅设置粘性阻尼器和同时设置粘性阻尼器和滞回阻尼器的基础隔震结构的抗震性能.研究表明:对于不同的输入地震波,能量法的地震响应预测值包络了多数时程分析的结果,能较好地预测基础隔震结构的地震响应值.在基础隔震结构设计中,建议在隔震层同时设置粘性阻尼器和滞回阻尼器,粘性阻尼器的阻尼比在0.3 ～0.4之间. 相似文献
10.
底部两层框架基础隔震建筑非线性动力分析 总被引：1，自引：0，他引：1
实际震害表明,建筑物主要受水平地震作用影响。本文基于有限元理论,采用大型有限元分析软件SAP2000 Non linear建立了底部两层框架上部砌体非隔震结构和基础隔震结构的实体模型,并采用非线性时程分析法对此模型进行了两个水平向地震作用的分析。结果表明,底部两层框架上部砌体结构采用基础隔震技术后,结构的水平地震反应明显低于相应非隔震结构。尤其是刚度突变的转换层,隔震后水平地震反应降低很多。 相似文献
11.
本文提出了一个近似分析具有滞迟耗能装置的高层建筑的方法。结果被模拟为一个有滞迟非线性支座的悬壁梁。其控制方程由Ｒｉｔｚ法导出，用等效线性化方法分析。 相似文献
12.
Kyung Hwan Cho Moon Kyum Kim Yun Mook Lim Seong Yong Cho 《Soil Dynamics and Earthquake Engineering》2004,24(11):839-852
The seismic response analysis of a base-isolated liquid storage tank on a half-space was examined using a coupling method that combines the finite elements and boundary elements. The coupled dynamic system that considers the base isolation system and soil–structure interaction effect is formulated in time domain to evaluate accurately the seismic response of a liquid storage tank. Finite elements for a structure and boundary elements for liquid are coupled using equilibrium and compatibility conditions. The base isolation system is modeled using the biaxial hysteretic element. The homogeneous half-space is idealized using the simple spring-dashpot model with frequency-independent coefficients. Some numerical examples are presented to demonstrate accuracy and applicability of the developed method.Consequently, a general numerical algorithm that can analyze the dynamic response of base-isolated liquid storage tanks on homogeneous half-space is developed in three-dimensional coordinates and dynamic response analysis is performed in time domain. 相似文献
13.
利用基于性能的结构可靠度分析方法,对基础隔震钢筋混凝土框剪结构进行分析研究。选取20条实际地震动记录,以0.2g为步长对结构地震动参数PGA进行调幅后,建立了140个结构-地震动样本空间。选取上部结构的最大层间位移角、隔震层位移为量化指标,对每一个样本进行动力非线性时程分析后,将结构响应进行统计得到结构在各地震动强度下超越极限破坏状态的概率,将其绘制成基础隔震钢筋混凝土框剪结构的易损性曲线并利用整体可靠度方法分析结构发生倒塌的可靠度指标。该方法直观地反映了结构发生倒塌的概率,为结构的地震损失评估提供依据。 相似文献
14.
Changhai Zhai Duofa Ji Weiping Wen Cuihua Li Weidong Lei Lili Xie 《地震工程与工程振动(英文版)》2018,17(2):277-291
Structures located in seismically active regions may be subjected to mainshock-aftershock (MSAS) sequences. Strong aftershocks significantly affect the hysteretic energy demand of structures. The hysteretic energy, EH,seq, is normalized by mass m and expressed in terms of the equivalent velocity, VD,seq, to quantitatively investigate aftershock effects on the hysteretic energy of structures. The equivalent velocity, VD,seq, is computed by analyzing the response time-history of an inelastic single-degree-of-freedom (SDOF) system with a varying vibration period subjected to 309 MSAS sequences. The present study selected two kinds of MSAS sequences, with one aftershock and two aftershocks, respectively. The aftershocks are scaled to maintain different relative intensities. The variation of the equivalent velocity, VD,seq, is studied for consideration of the ductility values, site conditions, relative intensities, number of aftershocks, hysteretic models, and damping ratios. The MSAS sequence with one aftershock exhibited a 10% to 30% hysteretic energy increase, whereas the MSAS sequence with two aftershocks presented a 20% to 40% hysteretic energy increase. Finally, a hysteretic energy prediction equation is proposed as a function of the vibration period, ductility value, and damping ratio to estimate hysteretic energy for mainshock-aftershock sequences. 相似文献
15.
M. C. Constantinou 《地震工程与结构动力学》1987,15(8):963-983
A simplified method of analysis of base-isolated structures supported on flexible soil is presented, in which the soil–base-isolated-structure system is represented by a SDOF oscillator supported on rigid soil. A parametric study illustrates the application and accuracy of the method. The results obtained lead to the conclusion that the simplified procedure that is presented is sufficiently accurate for purposes of preliminary design of base-isolated structures, and for studies to determine the feasibility of using base-isolation. 相似文献
16.
为准确全面地量化分析研究土木工程建筑中混凝土结构抗震稳定性,提出基于滞回曲线以及结构动力方程的混凝土结构抗震稳定性分析方法。首先采用滞回曲线描述混凝土结构在地震作用下的损伤情况,对滞回曲线模型拐点进行有效操作,确保动力方程对混凝土结构抗震稳定性进行有效分析。其次采用基于混凝土结构动力方程的抗震稳定性分析方法,对地震地面运动模型以及结构分析模型来分析混凝土结构的随机地震反应情况,得到混凝土结构随机反应的汇总量,在此基础上通过双参数的结构破坏模型,基于结构稳定性原理,获取运算混凝土结构抗震稳定性的概率表达式,再基于该表达式分析混凝土结构的抗震稳定性情况。实验结果说明,所提方法能够对土木工程建筑中不同类型混凝土构件抗震稳定性进行有效分析,分析结果准确且全面。 相似文献
17.
An analytical representation of the bilinear hysteretic characteristic is presented. Using this representation, the response of a single-degree-of-freedom bilinear hysteretic system subjected to non-stationary random excitation is examined by equivalent linearization. An ordinary differential equation is derived for the covariance matrix of the response. Numerical examples are presented and the accuracy of the approach is demonstrated. Extension of the approach to a wider class of hysteretic systems is discussed. 相似文献
18.
Timber structures are characterized by a pinching phenomenon that leads to reduced dissipative capability. A few hysteretic models have been proposed to simulate the mechanical behavior of timber structures, among which the one composed of a bilinear element and a slip element in parallel has been popular in practice. Based on this model, this paper expands on the existing seismic control design methodology to determine the capacity of hysteretic dampers for multi-story timber structures. The equivalent linearization method for a single-degree-of-freedom timber structure with added hysteretic damper is established and is verified through nonlinear timber history analysis over a wide range of structural parameters. The design formulas for determining the damper capacity for a multi-degree-of-freedom system are derived, based on the concept of adjusting the distribution of equivalent stiffness of structure. The seismic control design is applied to many buildings with randomly generated parameters and the effectiveness is confirmed through a nonlinear time history analysis with four sets of seismic excitations. An extended study has shown that the shear force pattern plays an important role in the seismic control design results and thus the performance of structures. The effectiveness of the control of residual deformations by adding dampers is also studied. 相似文献
19.
lvaro A. M. F. Cunha 《地震工程与结构动力学》1994,23(8):837-857
The stochastic equivalent linearization method has been significantly improved during the last two decades, leading to rather efficient and accurate estimates of the first- and second-order statistical moments of the random response process, even when the non-stationarity of the excitation and the hysteretic degrading non-linearities of the structural system are taken into account. The purpose of this paper, apart from presenting a short survey of the most relevant methods developed in this area, indicating their main restrictions, is to call attention to the remarkable possibilities of the equivalent linearization technique as the most powerful approximate method to deal with the seismic response analysis of MDOF non-linear building structures, deserving to be considered by the engineering codes in the near future as an appropriate formulation for that purpose. To illustrate the real interest of this method, several applications concerning a simple shear-building structural model are presented, considering columns with non-linear restoring forces, either bilinear elastic or hysteretic, and the results obtained by some computer programs developed on the basis of the equivalent linearization technique are compared with the estimates achieved by digital simulation in order to check the level of accuracy. Moreover, these results are also used to evaluate limit violation (failure) probabilities, based on the vulnerability function concept. 相似文献