共查询到18条相似文献，搜索用时 203 毫秒
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基于橡胶支座和滑板支座的水平力学性能,开发了一种新型多级隔震装置并介绍了该装置的组成、运动状态及力学模型。为了验证多级隔震装置在多水准地震作用下具有多级刚度的特性,设计了一幢相似比为1/10的四层混凝土框架结构,并根据结构模型设计了四套多级隔震装置进行了新型多级隔震结构振动台试验。试验与模拟结果表明:新型多级隔震装置隔震性能良好且在不同水准地震作用下能表现出多级抗震性能,相较于普通隔震装置,在大震下能较好的控制隔震层位移。针对不同多级隔震结构给出了多级隔震装置的最优参数的筛选流程,并基于某实际工程通过筛选流程选取了装置的最优参数。 相似文献
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隔震技术在提高多跨桥梁抗震性能方面已有广泛应用,然而传统隔震支座在近场脉冲地震动作用下容易产生残余位移较大、底部剪力水平较高、以及限位能力不足等问题。目前尝试解决上述问题主要有2个途径：一方面利用形状记忆合金(shape memory alloy, SMA)的隔震支座能有效控制峰值位移和残余位移,但同时会增加结构的内力响应;另一方面,利用负刚度(negative stiffness device, NSD)的隔震支座可以有效减小结构的内力响应,但可能会引起较大的残余位移。基于太平洋地震研究中心数据库提供的28条近场脉冲波,充分评估了间隙式SMA隔震支座和NSD隔震支座应用于多跨简支桥梁在四水准(小震、中震、大震和巨震)作用下的隔震性能。在此基础上,结合SMA与NSD各自的优点,提出一种间隙式SMA-NSD摩擦隔震支座并分析了其隔震性能。研究结果表明,该支座可显著降低NSD支座引起的残余变形并同时有效控制SMA支座引起的底部剪力。 相似文献
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《地震工程与工程振动》2015,(5)
为推动国内桥梁减隔震技术发展和促进相关规范完善,对中国、日本、美国等减隔震设计规范的发展历程、抗震设防目标、抗震设计和分析方法、构造措施及细节等进行对比分析,介绍了减隔震装置(支座)的性能要求和特性试验和原型试验技术要点。认为宜进一步在设计规范中细化设计方法、分析方法及构造措施要求等,重视减隔震装置性能检测及原型试验,增强抗震设计规范和技术标准之间的协调性。 相似文献
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《地震工程与工程振动》2017,(5)
近几十年桥梁减隔震技术在很多国家得到了广泛应用,已成为提高强震区桥梁抗震能力的重要手段。本文简要介绍了现有的桥梁减隔震装置,归纳了国内外经受过地震考验的多座隔震桥梁的抗震性能和震害表现,特别分析了2008年汶川大地震和2011年东日本大地震中的隔震桥梁及支座的抗震性能。根据减隔震桥梁的震害特征,总结了减隔震设计和应用是需注意的问题,包括减隔震设计方案选择、设计方法与构造要求、临近断层的设计挑战、减隔震装置耐久性等。最后展望了桥梁减隔震技术与理论的未来发展趋势,以促进对减隔震技术在桥梁工程领域的应用和发展。 相似文献
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《地震工程与工程振动》2015,(4)
主要研究基于推倒分析的普通减隔震支座连续梁桥的抗震性能评估方法。根据自适应的与质量成比例的推倒分析方法(AMPP)、MPA方法和时程分析方法(THA),评估了某常用减隔震支座连续梁桥的抗震性能。结果表明:AMPP方法可以成功地应用于常用减隔震支座桥梁的抗震性能评估,其对桥墩内力、支座位移和梁体位移的计算精度优于MPA方法。 相似文献
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为了研究温度对铅芯橡胶支座（LRB）隔震桥梁抗震性能的影响,以一座七跨连续梁桥为对象,考虑LRB在夏季和冬季不同温度下的力学特性,利用OpenSees对桥梁抗震性能进行研究。通过对不同温度下墩柱、支座及桥梁系统的地震易损性分析,获得了温度对铅芯橡胶支座隔震桥梁抗震性能的影响。结果表明:（1）与夏季相比,冬季低温降低了桥墩的延性及LRB的剪切变形和耗能能力,使地震作用时墩顶位移和支座变形均小于夏季,降低了LRB的减震效果;（2）冬季低温增大了地震作用时桥墩、LRB及桥梁系统在各个破坏状态的损伤概率,在中等及严重破坏状态时损伤概率相比夏季分别增加了8%和15%。在寒冷地区进行LRB隔震桥梁设计时,应考虑低温导致的LRB隔震效果降低对桥梁抗震性能的影响。 相似文献
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针对曲线桥梁在地震中因固定支座处及桥墩底部受力过大而破坏严重的现象,提出考虑支座摩擦滑移隔震的曲线桥梁抗震设计方法,通过大型振动台模型试验,研究曲线桥梁考虑支座摩擦滑移时的隔震机理。试验结果表明:支座摩擦滑移可有效减小地震作用下曲线桥梁的桥墩加速度响应,但同时会增加桥墩与梁体间的相对位移;曲线桥梁进行隔震设计后,桥墩的应变响应明显减小,证明该设计方法可有效避免地震作用下桥墩底部产生较大的损伤;最后,探讨了考虑支座摩擦滑移时曲线桥梁的隔震机理并与震害进行了对比验证。研究成果可为曲线桥梁的减震隔设计提供新的视角。 相似文献
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《地震工程与工程振动》2020,(4)
道庆洲桥是一座公轨两用双层变高钢桁组合桥梁,采用双曲面球型减隔震支座。该支座的竖向承载力为135 000 kN,超出桥梁双曲面球型减隔震支座规范的正常标准。为了研究此桥的抗震性能及其支座性能,本文设计和制作了安装有与实桥支座的竖向承载力相似比为1∶25的双曲面球型减隔震支座的双层变高度钢桁梁节段的缩尺模型,对其进行拟静力试验。得到了整个模型在不同支座轴压比下的滞回曲线、骨架曲线、刚度和水平承载力退化、耗能能力和滑动摩擦系数等抗震性能指标。试验结果表明:不同支座轴压比下,模型的滞回曲线饱满,呈现为平行四边形;与普通双曲面球型减隔震支座相比,支座的滞回性能相同;随着支座轴压比的增加,模型的水平承载能力、累积耗能、初始刚度和滑动摩擦系数也会相应增加,但对于水平承载力退化、刚度退化和等效黏滞系数影响较小;试验模型具有良好的抗震性能。 相似文献
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Sliding base‐isolation systems used in bridges reduce pier drifts, but at the expense of increased bearing displacements under near‐source pulse‐type earthquakes. It is common practice to incorporate supplemental passive non‐linear dampers into the isolation system to counter increased bearing displacements. Non‐linear passive dampers can certainly reduce bearing displacements, but only with increased isolation level forces and pier drifts. The semi‐active controllable non‐linear dampers, which can vary damping in real time, can reduce bearing displacements without further increase in forces and pier drifts; and hence deserve investigation. In this study performance of such a ‘smart’ sliding isolation system, used in a 1:20 scaled bridge model, employing semi‐active controllable magneto‐rheological (MR) dampers is investigated, analytically and experimentally, under several near‐fault earthquakes. A non‐linear analytical model, which incorporates the non‐linearities of sliding bearings and the MR damper, is developed. A Lyapunov control algorithm for control of the MR damper is developed and implemented in shake table tests. Analytical and shake table test results are compared. It is shown that the smart MR damper reduces bearing displacements further than the passive low‐ and high‐damping cases, while maintaining isolation level forces less than the passive high‐damping case. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Damage investigation of small to medium-span highway bridges in Wenchuan earthquake revealed that typical damage of these bridges included: sliding between laminated-rubber bearings and bridge girders, concrete shear keys failure, excessive girder displacements and even span collapse. However, the bearing sliding could actually act as a seismic isolation for piers, and hence, damage to piers for these bridges was minor during the earthquake. Based on this concept, an innovative solation system for highway bridges with laminated-rubber bearings is developed. The system is comprised of typical laminated-rubber bearings and steel dampers. Bearing sliding is allowed during an earthquake to limit the seismic forces transmitting to piers, and steel dampers are applied to restrict the bearing displacements through hysteretic energy dissipation. As a major part of this research, a quarter-scale, two-span bridge model was constructed and tested on the shake tables to evaluate the performance of this isolation system. The bridge model was subjected to a Northridge and an artificial ground motion in transverse direction. Moreover, numerical analyses were conducted to investigate the seismic performance of the bridge model. Besides the test bridge model, a benchmark model with the superstructure fixed to the substructure in transverse direction was also included in the numerical analyses. Both the experimental and the numerical results showed high effectiveness of this proposed isolation system in the bridge model. The system was found to effectively control the pier-girder relative displacements, and simultaneously, protect the piers from severe damage. Numerical analyses also validated that the existing finite element methods are adequate to estimate the seismic response of bridges with this isolation system. 相似文献
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The development of an expansion double spherical seismic isolation (DSSI) bearing by modifying the fixed DSSI bearing is described in this paper.The expansion DSSI bearing is characterized by its good ... 相似文献
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通过对分别采用板式支座和铅芯支座的2座3跨连续梁桥模型进行振动台试验,对比分析了这2类桥梁的动力特性、破坏过程及2种支座对连续梁桥地震反应的影响。研究结果表明：地震波特性对桥梁结构的地震反应有较大影响,在对桥梁结构进行抗震设计时,需选择合理的地震动输入;在地震强度较小时,板式支座的滑动能够起到一定的隔震效果,铅芯支座的隔震性能能得到较好的发挥;在地震强度较大时,铅芯支座的隔震性能不能得到很好的发挥,采用铅芯支座的桥梁地震反应不一定小于普通桥梁;通过合理的设计,2类桥梁都完全可以实现大震不倒的设防目标。 相似文献
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《地震研究进展（英文）》2022,2(4):100155
When the sliding bearing is fixed only at the top of the middle column of the underground structure, the cracks at the side end of the middle plate should be aggravated while the seismic damage of the mid-column should be alleviated. To enhance the seismic performance of the mid-plate, a new isolation design method has been mentioned while the elastic sliding bearings are set at the top of the mid-columns and between the side end of the mid-plate and the side wall at the same time. By establishing a nonlinear finite element analysis model for the static-dynamic coupling interaction system, the seismic response characteristics of the cast-in-place station structure without a sliding bearing have been analyzed and compared with those of the station structure with the sliding bearing fixed only at the top of the middle columns, and those of the station structure with sliding bearing be fixed between the mid-plate and the sidewall at the same time. The results show that the new isolation station structures suffer fewer earthquake damages at the mid-plate and mid-columns at the same time, which can improve the overall seismic performance of the subway station structure. 相似文献
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Effectiveness of a new semiactive independently variable stiffness (SAIVS) device in reducing seismic response of sliding base isolated buildings is evaluated analytically and experimentally. Through analytical and experimental study of force—displacement behaviour of the SAIVS device, it is shown that the device can vary stiffness continuously and smoothly between minimum and maximum stiffness. Passive sliding base isolation systems reduce interstorey drifts and superstructure accelerations, but with increased base displacements, which is undesirable, under large velocity near fault pulse type earthquakes. It is a common practice to incorporate non‐linear passive dampers into the isolation system to reduce bearing displacements. Incorporation of passive dampers, however, may result in increased superstructure accelerations and drifts; while, properly designed passive dampers can be beneficial. A viable alternative is to use semiactive variable stiffness systems, which can vary the period of the sliding base isolated buildings in real time, to simultaneously reduce bearing displacements and superstructure responses further than the passive systems, which deserves investigation. This study investigates the performance of a 1:5 scaled smart sliding base isolated building model equipped with the SAIVS device analytically and experimentally, under near fault earthquakes, by developing a new moving average non‐linear tangential stiffness control algorithm for control of the SAIVS device. The SAIVS device reduces bearing displacements further than the passive cases, while maintaining isolation level forces and superstructure responses at the same level as the passive minimum stiffness case, indicating the significant potential of the SAIVS system. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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基于动力学基本原理,建立非规则桥梁的多自由度动力简化模型,根据拉格朗日方程推导简化模型的动力方程,结合龙格—库塔方法,采用自编程序研究行波激励下非规则桥梁综合考虑支座摩擦滑移、结构碰撞等非线性因素作用时的抗震性能。结果表明,行波效应和碰撞效应的共同作用可使矮墩的弯矩需求增大;行波激励可使板式橡胶支座位移增大,地震波最后到达的桥墩其上方支座位移峰值增加最为明显;相比高墩,地震作用下矮墩上部的板式橡胶支座易发生滑动。因此非规则桥梁进行防碰撞设计时应考虑行波激励及支座摩擦,找出相邻结构的最大碰撞力,以指导设计。 相似文献
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Experimental study of the effect of restraining rim design on the extreme behavior of pendulum sliding bearings 
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下载免费PDF全文 《地震工程与结构动力学》2018,47(4):906-924
While the performance of sliding isolators has been extensively validated under typical levels of ground motion, there have been very few experimental studies on the extreme behavior of sliding isolation bearings when the displacement limit is reached. However, to appropriately design isolated systems, from selecting the displacement capacity of the bearing to sizing the superstructure members, the behavior of the bearing as it reaches, and in some cases exceeds, the displacement limit should be well understood. A series of shake table tests to investigate the extreme behavior of double pendulum sliding bearings under strong ground motions were conducted at McMaster University. One major difference in sliding bearings around the world is how the motion of the bearing is restrained at the bearing's displacement capacity. Scaled bearings with four different types of restraining rim designs were included, representing typical sliding restraining rims found in Europe, Japan, and the United States. Experimental observation shows that the restraining rim has a significant influence on the extreme behavior of sliding isolation bearing. Key response parameters such as impact force and uplift are evaluated and compared between the different sliding bearing designs. While the bearing with no rim bearing imparts the lowest forces to the superstructure, it loses its functionality at a lower amplitude input than all the other rim types. For the other rim designs, the impact forces are significantly higher but they remained operational although damaged. 相似文献