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为了研究铅芯橡胶支座(LRB)和板式橡胶支座(RB)对连续梁桥地震响应及隔震效果的影响,分别采用Bouc - Wen滞回恢复力模型模拟LRB的力-位移非线性特性,采用直线型恢复力模型模拟RB的本构关系,通过结构离散建立了非隔震、LRB隔震和RB隔震3种连续梁桥的有限元计算模型,运用四阶显式Runge - Kutta迭代法和Newmark时间积分法联合求解增量形式的全桥动力微分方程,并结合算例对3种连续梁桥有限元计算模型分别输入汶川地震波进行非线性时程对比分析.结果表明:LRB在控制梁体与支座位移,降低结构加速度和墩、台底内力响应方面均比RB的效果要显著;采用RB隔震后,梁体与支座的位移响应均较大,在桥梁隔震设计时要予以充分重视. 相似文献
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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
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Experimental Investigations on Laminated Rubber Bearings 总被引：1，自引：0，他引：1
Sarvesh?Kumar?JainEmail author Shashi?Kant?Thakkar 《Bulletin of Earthquake Engineering》2005,3(1):129-136
Increasing application of base isolation as a seismic protection method has subsequently increased its analytical and experimental studies. Being the most critical part of the base isolated buildings, accurate evaluation of structural properties and precise modeling of isolation devices is of utmost importance in predicting the response of the buildings during the earthquakes. This technical note is concerned with experimental study on laminated rubber bearings. Free vibration and harmonic base excitation tests are performed on a three-storey building model to evaluate the properties of the structure, efficiency of the system, and effect of base excitations. It is found that these experimental methods can effectively be used for this purpose. 相似文献
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The widespread use of sliding bearings for the seismic isolation of structures
requires detailed knowledge of their behavior and improved modeling capability under seismic conditions. The paper summarizes the results of a large experimental investigation on steel–PTFE interfaces, aimed at evaluating the effects of sliding velocity, contact pressure, air temperature and state of lubrication on the mechanical behavior of steel-PTFE sliding bearings. Based on the experimental outcomes, two different mathematical models have been calibrated, which are capable of accounting for the investigated parameters in the evaluation of the sliding friction coefficient. The first model is basically an extension of the model proposed by Constantinou et al. (1990)Journal of Earthquake Engineering, 116(2), 455–472, while the second model is derived from the one proposed by Changet al. (1990)Journal of Engineering Mechanics, 116, 2749–2763. Expressions of the model parameters as a function of bearing pressure and air temperature are presented for lubricated and non-lubricated sliding surfaces. Predicted and experimental results are finally compared. 相似文献
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For the purpose of accurately predicting the seismic response of base-isolated structures, an analytical hysteresis model for elastomeric seismic isolation bearings is proposed. An extensive series of experimental tests of four types of seismic isolation bearings—two types of high-damping rubber bearings, one type of lead-rubber bearing and one type of silicon rubber bearing—was carried out with the objective of fully identifying their mechanical characteristics. The proposed model is capable of well-predicting the mechanical properties of each type of elastomeric bearing into the large strain range. Earthquake simulator tests were also conducted after the loading tests of the individual bearings. In order to show the validity of the proposed model, non-linear dynamic analyses were conducted to simulate the earthquake simulator test results. Good agreement between the experimental and analytical results shows that the model can be an effective numerical tool to predict not only the peak response value but also the force–displacement relationship of the isolators and floor response spectra for isolated structures. © 1997 by John Wiley & Sons, Ltd. 相似文献
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An experimental study of a seismically isolated and a comparable non-isolated bridge is presented. The bridge model featured flexible piers, weighed 158kN and was tested on a shake table with an array of real and simulated seismic motions with peak acceleration in the range 0⋅1–1⋅1g. When isolated, the bridge deck was supported by four spherically shaped sliding bearings (known as Friction Pendulum System or FPS bearings) with friction coefficient under dynamic conditions in the range 0⋅07–0⋅12. The experimental results demonstrated a substantial improvement in the ability of the isolated bridge to sustain all levels of seismic excitation under elastic conditions. 相似文献
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Donatello Cardone Mauro Dolce Giuseppe Gesualdi 《Bulletin of Earthquake Engineering》2009,7(3):801-834
This paper presents a new approach for the evaluation of accurate lateral force distributions for the Linear Static Analysis
(LSA) of Base Isolated (BI-) buildings. In essence, the proposed lateral force distributions depend on a factor measuring
the degree of non- linearity of the Isolation System (IS) and on the ratio between the effective period of the BI-structure
(Tis) and the fundamental period of the Fixed Based (FB-) structure (Tfb). The proposed approach is fully compatible with the Direct Displacement-Based Design (DDBD) method, recently developed by
Priestley and co-workers. The proposed lateral force distributions have been derived from the results of a large number of
Nonlinear Time-History Analyses (NTHA), carried out on six numerical models of multi-storey buildings, differing in storey
number (3, 5 and 8, respectively) and fundamental period of vibration (from 0.25 to 0.8 s) in the fixed-base configuration.
A great variety of Isolation Systems (ISs), characterised by either Elasto-Plastic with Hardening (EPH) or Flag-Shaped (FS)
force-displacement behaviour, have been considered in the NTHA. The numerical parameters of the IS models have been varied
in such a way as to reproduce the actual mechanical behaviour of the main currently used ISs, including: (i) Lead Rubber Bearings
(LRB), (ii) High-Damping Rubber Bearings (HDRB), (iii) Friction Pendulum Bearings (FPB), (iv) combinations of flat Sliding
Bearings (SB) and Low-Damping Rubber Bearings (LDRB) and (v) Combinations of flat SB and re-centring devices based on Shape
Memory Alloys (SMA). Comparisons between the storey shear forces derived with the proposed method and those obtained from
NTHA clearly show the great improvements in the accuracy of LSA predictions, when using the proposed lateral force distributions. 相似文献