期刊文献+
共找到26篇文章
< 1 2 >
每页显示 20 50 100
A modified Kelvin impact model for pounding simulation of base-isolated building with adjacent structures 被引量:13
1
作者 Ye Kun Li Li Zhu Hongping 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第3期433-446,共14页
Base isolation can effectively reduce the seismic forces on a superstructure, particularly in lowto medium-rise buildings. However, under strong near-fault ground motions, pounding may occur at the isolation level bet... Base isolation can effectively reduce the seismic forces on a superstructure, particularly in lowto medium-rise buildings. However, under strong near-fault ground motions, pounding may occur at the isolation level between the baseisolated building (BIB) and its surrounding retaining walls. To effectively investigate the behavior of the BIB pounding with adjacent structures, after assessing some commonly used impact models, a modified Kelvin impact model is proposed in this paper. Relevant parameters in the modified Kelvin model are theoretically derived and numerically verified through a simple pounding case. At the same time, inelasticity of the isolated superstructure is introduced in order to accurately evaluate the potential damage to the superstructure caused by the pounding of the BIB with adjacent structures. The reliability of the modified Kelvin impact model is validated through numerical comparisons with other impact models. However, the difference between the numerical results from the various impact analytical models is not significant. Many numerical simulations of BIBs are conducted to investigate the influence of various design parameters and conditions on the peak inter-story drifts and floor accelerations during pounding. It is shown that pounding can substantially increase floor accelerations, especially at the ground floor where impacts occur. Higher modes of vibration are excited during poundings, increasing the inter-story drifts instead of keeping a nearly rigid-body motion of the superstructure. Furthermore, higher ductility demands can be imposed on lower floors of the superstructure. Moreover, impact stiffness seems to play a significant role in the acceleration response at the isolation level and the inter-story drifts of lower floors of the superstructure. Finally, the numerical results show that excessive flexibility of the isolation system used to minimize the floor accelerations may cause the BIB to be more susceptible to pounding under a limited seismic gap. 展开更多
关键词 structural pounding base-isolATION near-fault ground motions Kelvin impact model nonlinear damping
下载PDF
Seismic Responses of Asymmetric Base-Isolated Structures under Near-Fault Ground Motion 被引量:1
2
作者 叶昆 李黎 方秦汉 《Journal of Southwest Jiaotong University(English Edition)》 2008年第4期335-345,共11页
An inter-story shear model of asymmetric base-isolated structures incorporating deformation of each isolation bearing was built, and a method to simultaneously simulate bi-directional near-fault and far-field ground m... An inter-story shear model of asymmetric base-isolated structures incorporating deformation of each isolation bearing was built, and a method to simultaneously simulate bi-directional near-fault and far-field ground motions was proposed. A comparative study on the dynamic responses of asymmetric base-isolated structures under near-fault and far-field ground motions were conducted to investigate the effects of eccentricity in the isolation system and in the superstructures, the ratio of the uncoupled torsional to lateral frequency of the superstructure and the pulse period of near-fault ground motions on the nonlinear seismic response of asymmetric base-isolated structures. Numerical results show that eccentricity in the isolation system makes asymmetric base-isolated structure more sensitive to near-fault ground motions, and the pulse period of near-fault ground motions plays an import role in governing the seismic responses of asymmetric base-isolated structures. 展开更多
关键词 Asymmetric base-isolated structure Near-fault ground motion Far-field ground motion Nonlinear seismic response
下载PDF
Adaptive base-isolation of civil structures using variable amplification 被引量:3
3
作者 Kenneth K. Walsh Makola M. Abdullah 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2006年第2期223-233,共11页
Semi-active dampers are used in base-isolation to reduce the seismic response of civil engineering structures. In the present study, a new semi-active damping system using variable amplification will be investigated f... Semi-active dampers are used in base-isolation to reduce the seismic response of civil engineering structures. In the present study, a new semi-active damping system using variable amplification will be investigated for adaptive baseisolation. It uses a novel variable amplification device (VAD) connected in series with a passive damper. The VAD is capable of producing multiple amplification factors, each corresponding to a different amplification state. Forces from the damper are amplified to the structure according to the current amplification state, which is selected via a semi-active control algorithm specifically tailored to the system's tmique damping characteristics. To demonstrate the effectiveness of the VAD-damper system for adaptive base-isolation, numerical simulations are conducted for three and seven-story base-isolated buildings subject to both far and near-field ground motions. The results indicate that the system can achieve significant reductions in response compared to the base-isolated buildings with no damper. The proposed system is also found to perform well compared to a typical semi-active damper. 展开更多
关键词 adaptive systems AMPLIFICATION base-isolATION DAMPING earthquake resistant structures multistorybuildings seismic isolation structural control
下载PDF
Simple Method for Dynamic Responses of Soil-Pile-Isolated Structure Interaction System 被引量:1
4
作者 Yu Xu Zhuang Haiyang Liu Shuai 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第4期426-437,共12页
To investigate the effect of soil-pile-structure interaction(SPSI effect)on the dynamic response of a baseisolated structure with buried footings on a pile foundation,certain shake table tests are previously conducted... To investigate the effect of soil-pile-structure interaction(SPSI effect)on the dynamic response of a baseisolated structure with buried footings on a pile foundation,certain shake table tests are previously conducted.Based on the test results and the existing related studies,an efficient simplified model and a corresponding calculation method are verified for estimating the dynamic characteristics of a base-isolated structure with buried footings on a pile foundation with the SSI effect.In this method,the solutions by Veletsos and co-workers for a non-isolated structure with the SSI effect are verified and advanced for a base-isolated structure,and the solutions by Maravas and co-workers for a non-isolated structure on a pile foundation are introduced to consider the effect of the piles.By comparison with the shake table test,this work proves that the simplified method can efficiently estimate the dynamic responses of a base-isolated structure with buried footings on a pile foundation.Using parameter analysis,this work also shows that the dynamic characteristics of a non-isolated structure are quite similar to those of the base-isolated structure when the soil foundation is sufficiently soft,which means that the isolation layer gradually loses its isolation function as the soil foundation softens. 展开更多
关键词 soil-structure interaction(SSI) base-isolated structure seismic response shake table test simplified method
下载PDF
Numerical Analysis of Seismic Elastomeric Isolation Bearing in the Base-Isolated Buildings
5
作者 M. Jabbareh Asl M. M. Rahman A. Karbakhsh 《Open Journal of Earthquake Research》 2014年第1期1-4,共4页
Base isolation concept is currently accepted as a new strategy for earthquake resistance structures. According to different types of base isolation devices, laminated rubber bearing which is made by thin layers of ste... Base isolation concept is currently accepted as a new strategy for earthquake resistance structures. According to different types of base isolation devices, laminated rubber bearing which is made by thin layers of steel shims bonded by rubber is one of the most popular devices to reduce the effects of earthquake in the buildings. Laminated rubber bearings should be protected against failure or instability because failure of isolation devices may cause serious damage on the structures. Hence, the prediction of the behaviour of the laminated rubber bearing with different properties is essential in the design of a seismic bearing. In this paper, a finite element modeling of the laminated rubber bearing is presented. The procedures of modeling the rubber bearing with finite element are described. By the comparison of the numerical and the experimental, the validities of modelling and results have been determined. The results of this study perform that there is a good agreement between finite element analysis and experimental results. 展开更多
关键词 base-isolated structure SEISMIC ISOLATION BEARING LAMINATED RUBBER BEARING Finite Element Analysis
下载PDF
MRD与LRB相混合的结构振动控制 被引量:8
6
作者 张延年 刘斌 +1 位作者 李艺 范鹤 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2006年第1期95-98,共4页
磁流变阻尼器(MRD)利用磁流变液提供可控性是当今最有前途的半主动控制装置,附加MRD是铅芯橡胶垫(LRB)隔震结构的发展方向.因此提出3种MRD与LRB隔震混合方案,建立了MRD与LRB隔震混合结构的动力分析模型,推导出运动微分方程,对其进行时... 磁流变阻尼器(MRD)利用磁流变液提供可控性是当今最有前途的半主动控制装置,附加MRD是铅芯橡胶垫(LRB)隔震结构的发展方向.因此提出3种MRD与LRB隔震混合方案,建立了MRD与LRB隔震混合结构的动力分析模型,推导出运动微分方程,对其进行时程反应分析.以7层框架结构为例,采用瞬时最优控制算法分别对3种混合方案进行地震反应分析,与LRB隔震结构进行比较,各混合方案的各种地震反应均明显得到更好地控制,而混合方案3的控制效果最显著. 展开更多
关键词 振动控制 混合控制 隔震结构MRD lrb 恢复力模型
下载PDF
土-结构相互作用对LRB减震桥梁影响的分析 被引量:5
7
作者 刘云贺 赵晓娟 王克成 《西安理工大学学报》 CAS 2003年第1期13-17,共5页
探讨了地震作用下桩基础刚度对采用铅销橡胶支座 (L RB)桥梁减震效果的影响 ,提出以墩底弹簧约束模型模拟群桩基础的方法 ,建立了考虑地基刚度影响的桥梁非线性动力分析模型。算例的非线性时程分析结果表明 :结构设计中如采用刚性基础假... 探讨了地震作用下桩基础刚度对采用铅销橡胶支座 (L RB)桥梁减震效果的影响 ,提出以墩底弹簧约束模型模拟群桩基础的方法 ,建立了考虑地基刚度影响的桥梁非线性动力分析模型。算例的非线性时程分析结果表明 :结构设计中如采用刚性基础假设 ,即忽略土 -结构相互作用 ,对普通橡胶支座 (RB)和铅销橡胶支座 (L RB)都会使设计结果偏于安全 ,尤其对 L 展开更多
关键词 桥梁 lrb减震 土—结构相互作用 非线性分析
下载PDF
考虑竖向地震作用的LRB隔震结构优化设计 被引量:1
8
作者 张延年 郭鹏飞 +1 位作者 董锦坤 朱朝艳 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2009年第12期190-193,共4页
为了研究竖向地震作用对LRB隔震结构的影响,并改善其隔震效果,建立了耦合地震作用下LRB隔震结构的地震反应分析模型并推导出运动微分方程.以7层LRB隔震结构为例进行地震反应分析,研究结果表明当考虑竖向地震作用时,LRB隔震结构仍具有良... 为了研究竖向地震作用对LRB隔震结构的影响,并改善其隔震效果,建立了耦合地震作用下LRB隔震结构的地震反应分析模型并推导出运动微分方程.以7层LRB隔震结构为例进行地震反应分析,研究结果表明当考虑竖向地震作用时,LRB隔震结构仍具有良好的隔震效果,但地震反应有不同程度的增加,且其增量随着竖向地震作用的增加而增加.建立LRB隔震装置的参数优化设计模型,采用IHGA程序对结构的进行优化设计.结果表明,LRB隔震结构在各种工况下的各项地震反应均得到更好地控制. 展开更多
关键词 结构振动控制 lrb隔震结构 耦合地震作用 结构优化 遗传算法
下载PDF
LRB基础隔震结构在近断层脉冲型地震作用下的动力响应研究 被引量:27
9
作者 叶昆 李黎 《工程抗震与加固改造》 北大核心 2009年第2期32-38,42,共8页
对LRB(Lead Rubber Bearing)基础隔震结构在近断层脉冲型地震作用下的动力响应进行了系统参数研究。考虑到近断层脉冲型地震动记录数量的有限性,为了参数研究的方便,提出了人工合成近断层脉冲型地震动的方法,即以实际的常规地震波(即远... 对LRB(Lead Rubber Bearing)基础隔震结构在近断层脉冲型地震作用下的动力响应进行了系统参数研究。考虑到近断层脉冲型地震动记录数量的有限性,为了参数研究的方便,提出了人工合成近断层脉冲型地震动的方法,即以实际的常规地震波(即远场地震)为底波,在此基础上叠加上等效脉冲模型来模拟近断层脉冲型地震;以此为输入,系统研究比较了在近断层脉冲型地震和常规地震作用下,LRB基础隔震结构的动力反应特性、不同的近断层脉冲型类型以及近断层脉冲型地震动参数和LRB隔震系统力学性能对上部结构最大绝对加速度和隔震层最大位移的影响。研究表明:LRB基础隔震结构在近断层脉冲型地震作用下,上部结构最大绝对加速度和隔震层最大位移与常规地震作用下相比,均有较大增加,隔震范围有一定减小;近断层地震动的脉冲类型,以及脉冲周期对LRB基础隔震结构的动力反应有很大的影响。 展开更多
关键词 lrb基础隔震结构 近断层脉冲型地震 常规地震 动力响应
下载PDF
LRB隔震渡槽结构地震响应的简化计算方法 被引量:1
10
作者 叶昆 符蓉 李黎 《土木工程与管理学报》 2011年第3期119-123,共5页
为探究采用铅芯橡胶隔震支座的大型渡槽结构地震响应的简化分析计算方法,本文针对某大型隔震渡槽进行了7度顺槽向地震响应分析。比较了双质点双线性模型、单质点双线性模型、改进后的单质点双线性模型和有限元模型的计算结果。分析了槽... 为探究采用铅芯橡胶隔震支座的大型渡槽结构地震响应的简化分析计算方法,本文针对某大型隔震渡槽进行了7度顺槽向地震响应分析。比较了双质点双线性模型、单质点双线性模型、改进后的单质点双线性模型和有限元模型的计算结果。分析了槽墩刚度、阻尼比对计算结果的影响。分析计算表明改进后的单质点双线性模型计算简便并能够满足精度要求,可以运用于实际工程的初步设计中。 展开更多
关键词 铅芯橡胶隔震支座 渡槽结构 双线性模型
下载PDF
隔震板柱结构LRB参数研究 被引量:1
11
作者 张卫东 《低温建筑技术》 2007年第4期65-67,共3页
为提高板柱结构的抗震性能,将隔震技术应用于该结构体系,建立了三维非线性有限元模型。通过不同地震波激励下的地震反应,研究了铅芯橡胶支座动力参数对板柱结构隔震效果的影响规律,提出了其合理的取值范围和选择原则。
关键词 隔震 板柱结构 lrb动力参数
下载PDF
LRB基础隔震结构在极罕遇地震作用下的碰撞响应研究
12
作者 许立英 林友勤 +3 位作者 吴应雄 胡广杰 苏福庆 章永伟 《水利与建筑工程学报》 2022年第1期155-163,共9页
随着极罕遇地震作用的引入,有必要探讨基础隔震结构在极罕遇地震作用下是否还具有良好的抗震性能。采用改进的Kelvin碰撞分析模型和双线性恢复力模型,建立基础隔震结构与周围挡土墙碰撞的运动方程,用MATLAB进行非线性时程分析。基于非... 随着极罕遇地震作用的引入,有必要探讨基础隔震结构在极罕遇地震作用下是否还具有良好的抗震性能。采用改进的Kelvin碰撞分析模型和双线性恢复力模型,建立基础隔震结构与周围挡土墙碰撞的运动方程,用MATLAB进行非线性时程分析。基于非线性时程分析的结果,研究基础隔震结构在极罕遇地震作用下的碰撞响应。比较考虑碰撞和不考虑碰撞两种情况下,上部结构平均延性系数和隔震支座平均剪应变随隔震结构力学性能参数的变化曲线;不同碰撞参数下,上部结构平均延性系数和隔震支座平均剪应变随隔震结构力学性能参数的变化曲线。结果表明基础隔震结构在极罕遇地震作用下的碰撞控制了隔震支座的剪应变,但加剧了上部结构的动力响应。提高上部结构或者隔震体系的屈服承载力可以降低上部结构的碰撞响应,增加隔震缝宽度、提高隔震体系屈服承载力或者隔震支座直径可以降低碰撞发生的概率。 展开更多
关键词 lrb基础隔震结构 极罕遇地震 碰撞响应 碰撞模型 碰撞参数
下载PDF
Experimental and theoretical study on vibration control of base-isolation with energy transducer 被引量:2
13
作者 程树良 辛亚军 王焕定 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期165-171,共7页
In order to evaluate the effects of structural control and energy transition for the base-isolation with energy transducer (BIET), shaking table tests on a steel frame model (BIET system) with scale of 1:4 were c... In order to evaluate the effects of structural control and energy transition for the base-isolation with energy transducer (BIET), shaking table tests on a steel frame model (BIET system) with scale of 1:4 were conducted and the results were compared with the lead rubber beating (LRB) isolation system for the same model. Then numerical analysis of the system was carried out, in which the improved Wen analytic model was used to simulate the hysteretic law of transducers. The results show that the structural system can transform the partial earthquake energy to hydraulic energy ; furthermore, the effect of structural control can reach or be close to that of the LRB isolation system. The agreements between numerical analysis results and those of shaking table tests demonstrate the accuracy of the numerical model. 展开更多
关键词 base-isolation with energy transducer (BIET) structural control shaking table test hysteretic law numerical analysis
下载PDF
基础隔震结构的系统参数优化设计 被引量:7
14
作者 张延年 范鹤 +2 位作者 董锦坤 朱朝艳 李艺 《沈阳建筑大学学报(自然科学版)》 EI CAS 2006年第4期529-533,共5页
目的为了改善基础隔震结构的减震效果,实现基础隔震结构设计的可靠性和有效性,得到基础隔震结构的系统优化参数.方法建立了基础隔震结构的动力分析模型,推导出其运动微分方程;对标准遗传算法经常出现未成熟收敛、振荡、随机性太大和迭... 目的为了改善基础隔震结构的减震效果,实现基础隔震结构设计的可靠性和有效性,得到基础隔震结构的系统优化参数.方法建立了基础隔震结构的动力分析模型,推导出其运动微分方程;对标准遗传算法经常出现未成熟收敛、振荡、随机性太大和迭代过程缓慢等缺点进行改善,提出了改进混合遗传算法;建立基础隔震结构系统参数优化设计模型,使用改进混合遗传算法对7层LRB隔震结构的系统参数进行优化设计.结果优化后,LRB隔震结构的相对加速度峰值、相对速度峰值、相对位移峰值和层间剪力峰值分别比优化前有不同程度的降低.结论工程实例计算结果表明改进混合遗传算法对基础隔震结构的系统参数优化效果比较理想,基础隔震结构的各项地震反应均得到了更好地控制. 展开更多
关键词 结构振动控制 lrb隔震结构 结构优化 改进遗传算法 混合遗传算法
下载PDF
铅芯橡胶隔震双槽渡槽设计与动力分析 被引量:2
15
作者 丁晓唐 颜云燕 唐德嘉 《水电能源科学》 北大核心 2012年第1期96-99,27,共5页
结合南水北调中线工程,利用铅芯橡胶隔震技术对双洎河大型双槽渡槽进行隔震设计,采用Housner模型考虑水体与槽身流固耦合作用对其进行有限元动力分析。与非隔震渡槽相比,隔震渡槽的频率大幅降低;随隔震周期的增加,隔震渡槽振型保持不变... 结合南水北调中线工程,利用铅芯橡胶隔震技术对双洎河大型双槽渡槽进行隔震设计,采用Housner模型考虑水体与槽身流固耦合作用对其进行有限元动力分析。与非隔震渡槽相比,隔震渡槽的频率大幅降低;随隔震周期的增加,隔震渡槽振型保持不变;槽身底部剪力减小,支座位移增大。等效线性模型计算的地震响应极值大于双线性模型,偏安全。结果表明,铅芯橡胶隔震技术可显著降低渡槽结构的地震响应,且隔震周期越大,降幅亦越大。 展开更多
关键词 铅芯橡胶隔震 双槽渡槽 水工结构 动力分析 隔震周期
下载PDF
自动化码头低架桥抗震性能的有限元分析
16
作者 邱惠清 毛飞 卢凯良 《中国工程机械学报》 2010年第3期290-293,共4页
对上海振华重工股份有限公司提出的自动化码头方案中立体分配系统中的低架桥空间桁架钢结构进行了抗震性能分析.首先利用ANSYS软件分析了三种不同支撑形式低架桥钢结构的动力特性,包括模态分析和弹性时程分析.通过分析低架桥钢结构在两... 对上海振华重工股份有限公司提出的自动化码头方案中立体分配系统中的低架桥空间桁架钢结构进行了抗震性能分析.首先利用ANSYS软件分析了三种不同支撑形式低架桥钢结构的动力特性,包括模态分析和弹性时程分析.通过分析低架桥钢结构在两种不同的天然地震载荷激励下的支座反力与变形,研究了铅芯橡胶支座的隔振效果. 展开更多
关键词 自动化码头 空间桁架 支撑形式 铅芯橡胶支座 隔振效果
下载PDF
考虑SSI效应的基础隔震结构隔震性能参数分析 被引量:5
17
作者 宋进 熊峰 +2 位作者 吕洋 周光鑫 魏明宇 《地震工程与工程振动》 CSCD 北大核心 2019年第4期236-244,共9页
目前规范中关于隔震结构的分析及设计均采用刚性地基假定,忽略地基土刚度的影响。基于此,本文以软土场地上的LRB(Lead Rubber Bearing)基础隔震结构为研究对象,首先提出了同时考虑地基动力响应的频率相关性与隔震层非线性的土与基础隔... 目前规范中关于隔震结构的分析及设计均采用刚性地基假定,忽略地基土刚度的影响。基于此,本文以软土场地上的LRB(Lead Rubber Bearing)基础隔震结构为研究对象,首先提出了同时考虑地基动力响应的频率相关性与隔震层非线性的土与基础隔震结构系统简化模型。其次,利用反应谱分析的方法,揭示了屈重比、结构-地基刚度比、高宽比以及上部结构周期等参数对于系统水平向减震系数的影响规律。研究表明:软土地基上隔震结构存在最优屈重比,其值随上部结构周期增加而减小;地基土越软,隔震层的有效隔震效率越低;在软土地基上,对于周期较短的建筑能够达到更高的隔震目标,周期较长的建筑难以达到较高的隔震目标;地基土刚度对高宽比较小的结构影响较大。 展开更多
关键词 软土场地 SSI效应 lrb基础隔震结构 水平向减震系数 隔震效率
下载PDF
基于不同减震控制技术的框架结构抗震性能研究 被引量:5
18
作者 柳玉印 许文贤 +1 位作者 尹训强 卢明全 《工程抗震与加固改造》 北大核心 2020年第4期86-92,共7页
针对结构的抗震薄弱环节,减震技术在既有老旧建筑物加固改造以及新建建筑中的应用已日趋广泛,不同的减震控制技术对结构抗震性能的改善是研究的关键环节。本文以大连某医疗机构的小高层框架结构为研究对象,基于SAP2000有限元分析平台,... 针对结构的抗震薄弱环节,减震技术在既有老旧建筑物加固改造以及新建建筑中的应用已日趋广泛,不同的减震控制技术对结构抗震性能的改善是研究的关键环节。本文以大连某医疗机构的小高层框架结构为研究对象,基于SAP2000有限元分析平台,分别建立了设置铅芯橡胶隔震支座、软钢阻尼器以及混合控制技术的三维非线性动力分析模型。进而,在8度罕遇地震作用下,对三种工况条件下的层间剪力、顶部位移以及层间位移角等进行了综合对比分析。计算结果表明,双混控制技术较好地融合了两种减震技术优势,并可改善由于刚度分布不均匀所带来的不利影响,相较单控减震技术结构具有更为良好的减震效果。研究成果可为减震技术在既有老旧及新建框架结构的设计有一定的指导作用。 展开更多
关键词 软钢阻尼器 铅芯橡胶支座 混合消能控制 时程分析 框架结构
下载PDF
Nonlinear analysis of r.c. framed buildings retrofitted with elastomeric and friction bearings under near-fault earthquakes
19
作者 Mirko Mazza 《Earthquake Science》 CSCD 2015年第5期365-377,共13页
Reinforced concrete (r.c.) framed buildings designed in compliance with inadequate seismic classifi- cations and code provisions present in many cases a high vulnerability and need to be retrofitted. To this end, th... Reinforced concrete (r.c.) framed buildings designed in compliance with inadequate seismic classifi- cations and code provisions present in many cases a high vulnerability and need to be retrofitted. To this end, the insertion of a base isolation system allows a considerable reduction of the seismic loads transmitted to the super- structure. However, strong near-fault ground motions, which are characterised by long-duration horizontal pulses, may amplify the inelastic response of the superstructure and induce a failure of the isolation system. The above considerations point out the importance of checking the effectiveness of different isolation systems for retrofitting a r.c. framed structure. For this purpose, a numerical inves- tigation is carried out with reference to a six-storey r.c. framed building, which, primarily designed (as to be a fixed-base one) in compliance with the previous Italian code (DM96) for a medium-risk seismic zone, has to be retrofitted by insertion of an isolation system at the base for attaining performance levels imposed by the current Italian code (NTC08) in a high-risk seismic zone. Besides the (fixed-base) original structure, three cases of base isolation are studied: elastomeric bearings acting alone (e.g. HDLRBs); in-parallel combination of elastomeric and friction bearings (e.g. high-damping-laminated-rubber beatings, HDLRBs and steel-PTFE sliding bearings, SBs); friction bearings acting alone (e.g. friction pendulum bearings, FPBs). The nonlinear analysis of the fixed-base and base-isolated structures subjected to horizontal com- ponents of near-fault ground motions is performed for checking plastic conditions at the potential critical (end) sections of the girders and columns as well as critical conditions of the isolation systems. Unexpected high val- ues of ductility demand are highlighted at the lower floors of all base-isolated structures, while re-centring problems of the base isolation systems under near-fault earthquakes are expected in case of friction beatings acting alone (i.e. FPBs) or that in combination (i.e. SBs) with HDLRBs. 展开更多
关键词 R.c. base-isolated structures Elastomericbearings Friction bearings Nonlinear dynamic analysis
下载PDF
基于结构设计的LRB基础隔震结构水平向减震系数研究 被引量:9
20
作者 符蓉 叶昆 李绍进 《工程力学》 EI CSCD 北大核心 2012年第A01期130-135,共6页
现行的建筑抗震设计规范(GB50011-2010)中隔震结构的上部结构地震作用计算采用水平向减震系数的方法,不同的水平向减震系数对应着隔震后上部结构水平地震作用所对应的烈度分档。由于水平向减震系数与基础隔震系统的力学性能参数密相关,... 现行的建筑抗震设计规范(GB50011-2010)中隔震结构的上部结构地震作用计算采用水平向减震系数的方法,不同的水平向减震系数对应着隔震后上部结构水平地震作用所对应的烈度分档。由于水平向减震系数与基础隔震系统的力学性能参数密相关,但对于两者之间的变化规律所开展的研究较少。该文以目前国内外最为普遍的LRB基础隔震结构为研究对象,通过等效线性化和振型分解反应谱方法,建立起了LRB隔震系统力学性能参数和上部结构地震作用的水平向减震系数之间的数学关系式以及计算方法,提供给工程设计人员用于基础隔震结构的初步设计过程之中。通过参数研究发现:上部结构自振周期小于0.6s,可以实现隔震后上部结构的水平地震作用比非隔震时降低一度半,上部结构自振周期介于0.6s^1.0s之间,可以实现降低一度,上部结构自振周期大于1.0s,最多可以实现降低半度。 展开更多
关键词 lrb基础隔震结构 减震系数 等效线性化 结构设计 振型分解
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部