隔震层竖向刚度对高层基础隔震结构的影响

高层隔震建筑的隔震层在罕遇地震作用下会产生拉应力。本文通过对一栋20层的高层隔震结构,分别采用等拉压刚度模型和不等拉压刚度模型进行动力非线性时程分析,研究叠层橡胶隔震支座竖向刚度模型对高层基础隔震结构动力响应的影响。研究表明,超出线弹性工作范围后,竖向等拉压刚度模型将会低估隔震层的竖向位移量,低估上部结构的动力响应。     

变刚度钢管混凝土短柱隔震装置的试验分析与研究

对变刚度钢管混凝土短柱隔震装置在低周反复荷载试验中所出现的问题进行了阐述,指出了产生问题的原因,给出了较理想的装置形式。同时,为提高装置的隔震性能,笔者提出了第二梯队支座的概念,经过理论分析与试验证,说明带有第二梯队座的变刚度钢管混凝土短柱隔震装置具有良好的隔震性能。     

上部结构与基础隔震层偏心对结构地震响应的影响

随着基础隔震技术的发展,我国在高烈度地区广泛开展基础隔震技术的工程应用必将成为一种趋势,但由于建筑功能和建筑造型的丰富多彩,结构的质量中心和刚度中心也趋于分布不均匀,以三层的钢框架结构为分析模型,利用结构分析软件Sap2000对上部结构质量中心和隔震层质量中心、刚度中心分布不均匀的三种方案进行单向水平地震作用下的非线性时程分析,分析结果表明:上部结构质量中心与隔震层质量中心存在偏心距对结构的扭转效应以及地震响应有较大的影响,减小上部结构的偏心距对调整结构的水平地震响应的影响成效最为显著;对于隔震层而言,隔震层的刚度中心偏心距较质量中心偏心距对上部结构的影响更大,有效控制隔震层刚度中心的偏心距在隔震设计中会更加有效。     

基于隔震结构Benchmark模型的隔震层刚度分布分析研究

在隔震结构Benchmark模型的基础上,建立了相应的动力反应计算方法及计算程序,并在理想化隔震层刚度布置的情况下研究了隔震层水平刚度分布对基础隔震结构地震响应的影响.通过针对Benchmark模型设计的3种隔震方案的计算结果比较表明:当隔震层刚度中心靠近结构质心时,能显著降低结构的扭转反应,但同时增大了水平位移分量.文中在隔震结构Benchmark模型上建立的计算方法和结论为隔震体系计算和隔震方案设计提供了可靠的依据和途径.     

橡胶隔震支座力学性能试验研究

在自行研制的压剪试验装置上进行了橡胶隔震支座水平刚度和竖向刚度等力学性能的检测试验研究,试验结果为建筑结构基础隔震设计和橡胶支座设计改进提供了依据。试验检测的产品已用于多个建筑工程。     

变刚度滞变耗能与隔震联合控制框架结构实验研究

对原有变刚度滞变－摩擦隔震支座进行了改进，提出一种多级变刚度滞变耗能器，并进行了初步的试验研究。在此基础上，对一纯框架结构（1：5）模型进行了耗能与隔震的联合控制试验研究，试验结果表明，采用这种联合控制技术能降低不同大小地震下的结构反应，具有很强的适应性。     

高层隔震结构非线性地震响应分析及设计方法研究

高层隔震结构的分析理论和设计方法是目前隔震技术向高层建筑推广的2个关键理论问题。本文以高烈度区宿迁市已经竣工的高层隔震建筑阳光大厦为工程实例,对高层隔震结构的非线性地震响应分析方法进行了研究,包括隔震支座竖向不同拉压刚度的模拟、各种类型的隔震支座水平力学特性的准确模拟,以及不同地震动输入方式和输入角度对隔震支座受拉情况的影响分析等;在此基础上,对隔震层的设计方法进行了分析,提出了隔震层设计的基本原则,进而给出了控制隔震层设计的基本指标,包括隔震支座的长期面压、极值面压、隔震层偏心率等;最后,对高层隔震结构的相关构造要求进行了必要的说明。     

基础隔震结构在竖向荷载作用下的内力分布特点

以一个3跨4排柱建筑为例,对非隔震结构和隔震结构在竖向荷载作用下的内力分布特点进行了对比研究,其中考虑了隔震层顶部梁板结构的荷载、刚度以及结构的梁柱刚度比等因素的影响.研究中发现,与非隔震结构相比,隔震结构一层柱子的柱端弯矩明显增大,隔震层顶部梁的梁端弯矩与其倚载成正比等规律.同时提出了基于非隔震结构的隔震结构在竖向荷载作用下内力的计算方法和“隔震影响系数”的概念.即,隔震结构的内力等于非隔震结构的内力乘以“隔震影响系数”.其中还进一步对“隔震影响系数”的影响因素进行了定量研究,得出了“隔震影响系数”的计算公式.本文所提出的计算方法与隔震结构在水平地震荷载作用下的内力计算方法思路一致,因此,该方法也进一步完善了隔震结构的设计理论.     

多级串联非比例阻尼隔震结构地震响应分析

建立了多级串联非比例阻尼隔震结构动力分析模型;引用分区瑞利阻尼模型将非比例阻尼矩阵分解为瑞利阻尼矩阵和体现非比例阻尼的余项阻尼矩阵,推导出结构的阻尼矩阵;并编制了MATLAB动力时程分析程序,对一实际隔震工程进行地震响应分析.结果表明:随着下部结构刚度的增加,结构的层剪力比和隔震层位移响应峰值均趋向于基础隔震结构的对应值;当下部结构为一层,且层间刚度大于上部结构底层层间刚度4～6倍时,可以近似按基础隔震结构进行动力分析.     

变刚度钢管混凝土短柱隔震装置的性能研究

本文对变刚度钢管混土短柱震的滞回收性进行了理论分析和试验验证。对装置的隔震作用以及耗能特性进行了讨论通过低周反复荷载试验,证了分析的正确性。同时,试验还证明,变刚度钢管混凝土短柱震装置能很好的地耗散能量,从而减小地震反应,作者认为,该是一种价格性能比较优越的隔震装置,在工程实践中将有广阔的应用与推广前景。     

Study on effects of damping in laminated rubber bearings on seismic responses for a ⅛ scale isolated test structure

The effects of damping in various laminated rubber bearings (LRB) on the seismic response of a ?‐scale isolated test structure are investigated by shaking table tests and seismic response analyses. A series of shaking table tests of the structure were performed for a fixed base design and for a base isolation design. Two different types of LRB were used: natural rubber bearings (NRB) and lead rubber bearings (LLRB). Three different designs for the LLRB were tested; each design had a different diameter of lead plug, and thus, different damping values. Artificial time histories of peak ground acceleration 0.4g were used in both the tests and the analyses. In both shaking table tests and analyses, as expected, the acceleration responses of the seismically isolated test structure were considerably reduced. However, the shear displacement at the isolators was increased. To reduce the shear displacement in the isolators, the diameter of the lead plug in the LLRB had to be enlarged to increase isolator damping by more than 24%. This caused the isolator stiffness to increase, and resulted in amplifying the floor acceleration response spectra of the isolated test structure in the higher frequency ranges with a monotonic reduction of isolator shear displacement. Copyright © 2002 John Wiley & Sons, Ltd.     

Investigation of the seismic response of high‐rise buildings supported on tension‐resistant elastomeric isolation bearings

In many applications of seismic isolation, such as in high‐rise construction, lightweight construction, and structures with large height‐to‐width aspect ratios, significant tension forces can develop in bearings, raising concerns about the possible rupture of elastomeric bearings and the uplift of sliding bearings. In this paper, a novel tension‐resistant lead plug rubber bearing (TLRB) with improved tension‐resisting capabilities is developed and experimentally and numerically assessed. This TLRB consists of a common lead plug rubber bearing (LRB) and several helical springs. After describing the theory underlying the behavior of the TLRB, the mechanical properties of reduced‐scale prototype bearings are investigated through extensive horizontal and vertical loading tests. The test results indicate that TLRBs can improve the shear stiffness and tension resistance capacity even under significant tensile loads. A series of shaking table tests on scaled models of high‐rise buildings with different aspect ratios were conducted to investigate the dynamic performance of the TLRB and the seismic responses of base‐isolated high‐rise buildings. Three different cases were considered in the shaking table tests: a fixed base condition and the use of TLRB and LRB isolation systems. The results of the shaking table test show that (a) base‐isolated systems are effective in reducing the structural responses of high‐rise buildings; (b) an isolated structure's aspect ratio is an important factor influencing its dynamic response; (c) TLRBs can endure large tensile stresses and avoid rupture on rubber bearings under strong earthquakes; and (d) the experimental and numerical results of the responses of the models show good agreement. Copyright © 2016 John Wiley & Sons, Ltd.     

Dynamic parameter identification for non-linear isolation systems in response spectrum analysis

The response spectrum method has been widely used in earthquake engineering design, but cannot be directly applied to non-linear systems such as the lead-filled rubber bearing used in base isolation systems. An appraoch to determine the equivalent linearized stiffness and damping coefficient of the lead-filled rubber bearing by use of the results of shaking table tests is developed. Comparisons of time histories for the equivalent linear systems and the actual model show the method gives accurate maxima for displacement and acceleration and at the appropriate times. It is found that the identified parameters vary with the maximum deformation and the simplified formulae that can optimally describe the variations are derived. Using these formulae, an iterative algorithm using the response spectrum method to calculate the dynamic response of buildings isolated by lead-filled rubber bearings is also presented.     

平扭耦联隔震体系隔震支座阻尼分布影响分析

为了研究铅芯橡胶隔震支座的阻尼分布对平扭耦联隔震体系隔震效果的影响,本文对一个三层两跨钢框架,通过调整上部结构负重块位置及下部铅芯橡胶隔震支座的分布位置,进行不同偏心工况下平扭耦联隔震体系地震模拟振动台试验,获得了不同偏心工况、不同阻尼分布情况下结构位移和加速度的时程曲线。试验和分析表明:隔震层阻尼中心与上部结构的质心位置接近,或者增大隔震层的阻尼半径,可显著地降低上部结构的扭转反应。     

Shaking table test and analysis method on ultimate behavior of slender base‐isolated structure supported by laminated rubber bearings

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.     

低硬度橡胶隔震支座各种相关性及老化徐变特性

作者系统地对低硬度橡胶隔震支座的材料和力学性能进行了试验研究。研究使用的低硬度橡胶隔震支座分18种规格，总计近30个大直径隔震支座。研究内容涉及低硬度橡胶隔震支座的基本力学性能；温度、压力、剪切变形、老化和徐变等相关性；压缩界限，屈曲及极限剪切变形等界限性能以及橡胶材料性能和隔震工程应用等方面。本文主要介绍低硬度橡胶隔震支座的压力、剪切变形、温度对支座刚度、阻尼等力学性能的影响，同时还对隔震支座的老化及徐变特性进行了试验研究，确定低硬度橡胶使用60年后的力学性能变化率。文中同时提出了低硬度橡胶支座的温度修正方程，并提出了隔震结构地震反应分析时支座刚度和屈服荷载变化的取值范围。     

村镇隔震砌体结构振动台试验方案设计研究

为使铅芯橡胶支座隔震技术应用于村镇砌体结构,将隔震层设置于地坪以上,本文给出了隔震构造的具体做法。选取典型村镇2层未设构造柱的砖砌体结构房屋为试验原型,按1:2缩尺,设计有隔震层和无隔震层的振动台对比试验。首先采用反应谱分析方法,对隔震和非隔震结构分别选取三条地震波,然后通过数值分析,研究隔震和非隔震结构在输入不同地震波时的地震反应规律,根据数值模拟的分析结果设计结构振动台试验中的传感器布置和加载方案。本文设计的砌体隔震振动台试验方案已试验成功,可为振动台试验设计和研究提供参考。     

新型多级隔震装置试验及最优参数分析

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。     

Experimental investigation on the seismic response of a steel liquid storage tank equipped with floating roof by shaking table tests

In this paper, the effectiveness of the base isolation on steel storage tanks has been investigated through numerical models and then checked by shaking table tests on a reduced scale (1:14) model of a real steel tank, typically used in petrochemical plants. In the experimental campaign the floating roof has also been taken into account. The tests have been performed on the physical model both in fixed and isolated base configurations; in particular two alternative base isolation systems have been used: high‐damping rubber bearings devices and sliding isolators with elasto‐plastic dampers. Finally, a comparison between experimental and numerical results has also been performed. Copyright © 2009 John Wiley & Sons, Ltd.     

复合隔震结构模型振动台试验研究

作者对一个二层复合隔震结构钢框架模型进行了振动台试验,该模型采用夹层橡胶支座与摩擦滑移支座并联组合作为隔震层,既能提供足够的弹性恢复力,又具有良好的结构耗能能力。试验测得结构各项动力响应,并将软件计算数据与试验数据进行了比较,结果表明复合隔震结构的加速度反应小,楼层层间位移也较小,上部结构基本为平动,结构耗能能力显著,而且软件可以很好地模拟结构的地震反应规律。