位移放大型黏滞阻尼伸臂桁架减震效果及动力试验研究

为提高黏滞阻尼伸臂桁架在地震作用下的耗能效率,设计了一种带位移放大装置的黏滞阻尼伸臂桁架。对分别设置传统型和位移放大型黏滞阻尼伸臂桁架的超高层结构进行有限元分析,对比了结构的地震响应及阻尼器的工作状态。通过动力荷载试验,考察两种黏滞阻尼伸臂桁架的滞回性能,对比阻尼器的位移及耗能,研究位移放大系数的变化规律,分析伸臂桁架刚度对黏滞阻尼伸臂桁架工作效率的影响。结果表明：相比传统型黏滞阻尼伸臂桁架,采用位移放大型黏滞阻尼伸臂桁架可将阻尼器的耗能效率提高至原来的1.5~1.8倍,使结构获得更好的减震效果;位移放大型黏滞阻尼伸臂桁架滞回曲线光滑、对称、饱满,具有良好的工作性能,且能有效放大阻尼器的工作位移并增大耗能;提出了黏滞阻尼伸臂桁架的位移放大系数的计算式,计算值与试验值吻合较好;为保证黏滞阻尼伸臂桁架的工作效率,建议伸臂桁架的刚度比取值不小于9。     

简谐激励下非线性黏滞阻尼调频质量阻尼器减振结构的稳态响应分析

对非线性黏滞阻尼在调频质量阻尼器(TMD)中的应用进行了研究。基于慢变参数法推导简谐激励下采用非线性黏滞阻尼调频质量阻尼器减振结构位移的稳态响应解析解,进而研究其优化参数求解公式。以主结构位移动力放大系数为目标,对线性和非线性黏滞阻尼TMD的减振效果进行了对比分析,结果表明:非线性黏滞阻尼TMD的减振效果要优于线性的,其最优阻尼比受到激励幅值的影响。     

超高层建筑结构加强层耗能减震技术及连接节点设计研究

在框架-核心筒结构体系中,加强层可显著提高结构抗侧刚度、减小结构侧移,但会带来结构刚度、内力突变等不利影响。以某超高层建筑为工程背景,研究了黏滞阻尼器在伸臂桁架体系中的应用及在多遇地震和罕遇地震作用下的减震效果,研究了设置黏滞阻尼器的环带桁架在超高层建筑中的较优位置和减震效率。结果表明：黏滞阻尼器在伸臂桁架结构中的设置可以减小核心筒剪力墙的塑性损伤,减小结构的动力响应;设置黏滞阻尼器的环带桁架宜布置在层间相对速度大的位置,随超高层结构高度增加,阻尼器的减震效率降低。通过对伸臂桁架与外框柱、核心筒连接节点的设计及构造的分析,提出了连接节点的设计建议。     

高层减震结构地震响应及方案优化研究

针对某高层建筑结构,利用ETABS有限元分析软件建立计算模型,探讨原结构和设置黏滞阻尼器的减震结构在多遇地震作用下的抗震性能,通过进行五种黏滞阻尼器布设方案下结构响应的比较,以不同的控制函数为目标,进而优化黏滞阻尼器的布设位置。结果表明,黏滞阻尼器在保证不增加结构刚度的基础上,通过提供附加阻尼,能有效协助结构耗散地震输入的能量,降低了结构的动力响应,起到了很好的减震效果。同时,在考虑黏滞阻尼器的布设位置时,应根据结构的实际动力响应和变形特性综合确定,并且考虑结构的功能需求以获得最佳的减震效果。     

建筑结构空间减震性能优化技术研究

针对高层建筑结构抗震问题,研究基于黏滞阻尼器建筑结构空间抗震性能优化技术。论文考虑黏滞阻尼器阻尼参数、位置布置等因素,并从两方面对建筑结构抗震反应影响进行分析。通过设置不同方案的仿真实验,探究建筑结构的抗震性能。最终实验结果表明,黏滞阻尼器阻尼指数较大时,其消能减震结构的耗能减震性能更优;对黏滞阻尼合理布置可以改善建筑结构的抗震性能。     

基于黏滞阻尼墙的高层建筑结构集成优化设计

黏滞阻尼墙是一种效率高的新型建筑结构消能减振部件,对于地震响应和风振动响应均有较好的减振效果,其为结构提供附加阻尼比可降低结构构件内力,从而为结构的构件设计提供了优化空间。提出一种基于黏滞阻尼墙的高层建筑结构集成优化设计方法,依据高层建筑结构构件的抗震性能目标及构件尺寸控制条件,加入黏滞阻尼墙对结构构件进行优化。以某300 m带环带桁架的框架核心筒超高层建筑为例,优化布置黏滞阻尼墙并且进行结构构件优化设计。结果表明,黏滞阻尼墙对高层建筑结构集成的优化可为结构主体带来经济性。     

黏滞阻尼伸臂桁架在超高层结构中的应用研究

黏滞阻尼伸臂桁架是针对核心筒-伸臂桁架结构将黏滞阻尼器竖向布置于伸臂桁架端部的一种消能减震技术,对位于高烈度抗震设防区的超高层框架-核心筒结构,采用该技术不仅可以有效地降低地震作用,还可以避免传统刚性伸臂桁架所带来的不利影响。为研究黏滞阻尼伸臂在超高层结构中的减震规律,对设置黏滞阻尼伸臂的超高层框架-核心筒结构进行减震作用分析,同时研究伸臂桁架刚度以及阻尼器参数对减震效果的影响。结果表明:黏滞阻尼伸臂具有附加阻尼和等效动刚度双重减震作用;综合考虑减震效果和经济性,伸臂桁架存在最优刚度;阻尼指数越小,减震效果越好;阻尼系数存在较优区间,使得黏滞阻尼伸臂取得较好的减震效果。     

基于黏滞阻尼器耗散功率的超高层结构风振设计方法北大核心CSCD

针对超高层建筑结构抗风设计中黏滞阻尼器参数设计问题,推导出黏滞阻尼器的功率计算表达式和功率需求表达式,并研究了黏滞阻尼器的层位移放大系数,给出了黏滞阻尼器控制超高层结构风振的功率设计方法。以两幢超高层结构为例,对黏滞阻尼器控制超高层结构风振的功率设计流程进行逐步实现,对设计方法的可行性和误差进行分析,结果表明,采用功率设计方法进行消能减振初步设计可达到预期减振目标。     

无轴黏滞阻尼器的性能试验及有限元分析

提出一种无轴黏滞阻尼器,其基本原理是通过油腔本身的变形驱使黏滞流体往返通过阻尼孔而耗散能量。通过性能试验和有限元分析,初步验证了该阻尼器的构造方案是可行的。基于结构振动控制Benchmark模型对该类型阻尼的减振性能进行研究,结果表明该类阻尼器具有很好的减振效果。     

超高层建筑结构放大型黏滞消能伸臂减震效果研究

为提升超高层建筑结构的抗震性能,提出了一种可充分发挥阻尼器耗能能力的放大型黏滞消能伸臂减震装置,该装置通过增加菱形转动机构,将核心筒与外框架之间竖向相对变形进行二次放大,以增大对超高层结构的动力响应的控制效果。基于某案例工程超高层结构,对其采用放大型黏滞伸臂方案、传统黏滞伸臂方案和抗震方案进行了弹塑性时程分析对比。结果表明：相比传统黏滞伸臂,放大型黏滞伸臂由于菱形放大装置的转动,阻尼器的耗能效果得到进一步提升,对主体结构的层间位移角、基底剪力等地震响应和塑性损伤均具有良好的控制效果,综合提升了阻尼伸臂系统的耗能效果。     

Structural performance and cost analysis of wind-induced vibration control schemes for a real super-tall building

To evaluate different energy dissipation systems used to control wind-induced vibrations of a 456 m super-tall building in fluctuating wind excitations, the finite element (FE) method was employed to simulate the dynamic responses of the building. A series of wind tunnel pressure tests were conducted on a 1:450 scale model to determine the wind forces acting on the super-tall building. A FE model was also constructed and mass, damping and stiffness matrices were subsequently formulated as an evaluation model for numerical analysis. The evaluation model was further simplified to a state reduced-order system using the state order reduction method. Three different vibration control schemes, namely a tuned mass damper (TMD) system, a system containing only nonlinear viscous dampers and a hybrid control system combining TMD and viscous dampers, were examined through simulations with respect to their effectiveness in reducing the accelerations at the top of the building. Furthermore, a cost evaluation was conducted to determine the most economical structural design and vibration control scheme. The results show that the wind-induced vibrations of the analysed building can be controlled effectively by all the three examined schemes, while the hybrid control scheme and the scheme containing only viscous dampers further reduce the wind-induced vibration to satisfy a more stringent criterion for a six-star hotel. In addition, the hybrid vibration control scheme is also the most cost-effective among the examined schemes.     

考虑参数随机性的高层建筑风振舒适度的非线性黏滞阻尼器优化布设

以顶层加速度作为概率特征量,建立目标函数,分别采用基于随机等效线性化系统的频域方法和基于概率密度演化理论的非线性系统时域方法,进行了考虑结构参数随机性的高层建筑风振舒适度控制的黏滞阻尼器优化布设研究。结果表明：在总黏滞阻尼器系数相同的条件下,以顶层加速度标准差和失效概率为目标函数的黏滞阻尼器优化布设方案,在确定性激励作用下均能显著降低结构的风振响应,且相对于未优化的阻尼器均匀满布方案更经济、更有效。以加速度标准差为目标函数的传统阻尼器优化布设本质上是确定性分析方法,对结构可靠度的提高作用有限,而以加速度失效概率为目标函数的阻尼器优化布设,以结构响应的概率密度函数为优化对象,能显著地提高结构的可靠度,有利于改善高层建筑结构的风振舒适度性能。     

高层建筑结构的风振阻尼控制分析与设计方法

本文首先分析了阻尼比对结构风振反应的控制效果,重点讨论了阻尼比对风振脉动增大系数的减小效果和具体计算方法,给出了便于工程实际应用的阻尼比为10%～30%的风振脉动增大系数随基本风压和结构基本周期变化的计算图表。结果表明,结构阻尼比增大,风振脉动增大系数明显减小。其次,分析了结构耗能减振系统的附加阻尼特性,给出了调频质量阻尼器(TMD)、调频液体阻尼器(TLD)和速度线性相关型耗能器附加给结构阻尼比的实用计算公式。最后给出了100层钢结构分别设置TMD和线性粘滞阻尼器的风振控制分析和设计实例。实例结果表明,两种被动阻尼控制系统对结构最大位移和最大加速度控制效果相同,可以达到40%～55%,同时说明了本文提出的方法可以方便地用于大型结构的风振阻尼控制分析和设计。     

Dynamic characteristics and viscous dampers design for pile‐soil‐structure system

A series of large‐scale shaking table tests are conducted on tall buildings with and without energy dissipation devices on soft soils in pile group foundations, representing pile‐soil‐structure interaction (PSSI) system and the corresponding fixed‐base situations. The superstructure is a 12‐story reinforced concrete (RC) frame. The dynamic characteristics of the test models show that the frequencies decrease and the damping ratio increase in PSSI system by comparison with the fixed‐base structures. The mode shapes of PSSI system are different from that under fixed‐base condition, and the mode shapes of structure without dampers change greater than that with energy dissipation devices under various white noises. An improved method for structural dynamic characteristics, considering the impedance function of piles, is developed to address the issue of modal parameters with PSSI effect. In addition, the structural dynamic parameters of the large‐scale shaking table tests are identified using the modification method and other regulation methods, demonstrating that the improved approach is highly accurate and effective. Subsequently, a design procedure for viscous dampers of structures with PSSI effect is presented based on the dynamic characteristics of the system. Finally, the dynamic responses of the structure with viscous dampers in the practical engineering are decreased effectively, indicating the good performance of designed viscous dampers. The numerical results also show that the damping efficiency of interstory drift is larger than the acceleration and interstory shear force. Therefore, the improved modal parameters method, validated through a series large‐scale shaking table tests, is applicable for identifying dynamic characteristics of pile‐soil‐structure with energy dissipation devices system. The design procedure of viscous dampers, proved by a reinforced concrete frame structure located on a practical Shanghai soft site, can be employed to design the viscous dampers considering seismic PSSI effect.     

汶川县人民医院带粘滞阻尼器结构耗能减震设计

汶川医院采用现浇钢筋混凝土框架结构,考虑其功能重要、结构不规则、抗震要求高等特点,在四周设置了46个K型粘滞阻尼器支撑,通过ETABS计算分析表明设置阻尼器能显著降低结构的响应,提高结构抗震性能,最后讨论了计算粘滞阻尼器结构附加阻尼比的简化使用算法。     

Vibration control study on a supertall building

Vibration control of a 288‐m supertall building with connective structure is studied in this work. Fluctuating wind time series of the structure in forward and reverse Y‐direction in a 10‐year frequency are simulated by modified auto‐regressive method (AR method) to perform wind vibration analysis, and six minor and major earthquake waves are provided by building designer to perform earthquake analysis. Three vibration control schemes with nonlinear viscous dampers are proposed to control structural dynamic responses under wind and earthquake excitations. The dynamic responses of the structure with the proposed control schemes in wind and earthquake excitations are investigated and their vibration control effects are analysed comparatively. The study results show that the modified AR method is reliable and effective for simulating the fluctuating wind exerted on the building. The excessive dynamic responses induced by wind and earthquake excitations can be controlled effectively by the proposed schemes. The peak acceleration of top storey can be reduced by almost 40% for the proposed control schemes in wind excitation. The elastic working state of the connective body between the high tower part and the low tower part in major earthquakes can also be ensured totally. So, the validity and feasibility of the proposed schemes in reducing structural vibration responses can be fully approved. Some suggestions about structural analysis and design under wind and earthquake excitations are proposed. Copyright © 2010 John Wiley & Sons, Ltd.     

Earthquake response control of a super high‐rise structure subjected to long‐period ground motions via a novel viscous damped system with multilever mechanism

A novel viscous damped system and its principles are proposed in the paper. It is a novel viscous damped system with multilever mechanism that can improve the energy dissipation capacity of conventional viscous dampers. In order to compare the damping effects of the novel viscous damper with that of the conventional viscous damper, a shaking table test of a three‐story steel frame structure is performed. Testing results indicate that the novel viscous damped system is more efficient. The elastic time‐history analysis of a super high‐rise frame‐core tube structure is studied under the frequently occurring earthquake. Dynamic loads take two groups of ground motions with different period characteristics into account. Main response values such as base shear, interstory drift, and acceleration factor under long‐period ground motions are apparently larger than the seismic results due to standard ground motions. Responses between the undamped structure and the damped structure with conventional viscous dampers or the latest products are compared. It is concluded that the proposed viscous damped system can perform more effectively in reducing high‐rise structural responses subject to long‐period ground motions.     

Evaluation of a developed bypass viscous damper performance

In this study, the dynamic behavior of a developed bypass viscous damper is evaluated. Bypass viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other side of the inner piston. Accordingly, the viscosity coefficient of the damper can be adjusted using geometrical dimensions of the hose. Moreover, the external orifice acts as a thermal compensator and alleviates viscous heating of the damper. According to experimental results, Computational Fluid Dynamic (CFD) model, a numerical formula and the simplified Maxwell model are found and assessed; therefore, the verification of numerical and computational models are evaluated for simulating. Also, a simplified procedure is proposed to design structures with bypass viscous dampers. The design procedure is applied to design an 8-story hospital structure with bypass viscous dampers, and it is compared with the same structure, which is designed with concentric braces and without dampers. Nonlinear time history analyses revealed that the hospital with viscous damper experiences less structural inelastic demands and fewer story accelerations which mean fewer demands on nonstructural elements. Moreover, seismic behaviors of nonstructural masonry claddings are also compared in the cases of hospital structure with and without dampers.     

设置黏滞阻尼器的悬挂减振结构振动台试验研究

通过对设置黏滞流体阻尼器的悬挂结构进行地震模拟振动台试验,分析了主结构与悬挂楼面的质量比、连接方式以及阻尼器分布对悬挂结构模型的频率、阻尼比和结构响应的影响。试验结果表明：与刚性杆连接的常规悬挂结构相比，采用阻尼器连接主结构和悬挂楼面，可改变结构频率，提高结构振型阻尼比，且模型前3阶振型主要表现为悬挂楼面剪切变形；悬挂减振结构主结构的位移峰值响应小于常规悬挂结构，略小于无连接的自由悬挂结构；当悬挂楼段质量较大时，减振效果更好；与自由悬挂结构相比，阻尼器连接的悬挂减振结构能较好地抑制悬挂楼面相对于主结构的位移和悬挂楼面的层间位移；当悬挂楼面侧向刚度较小时，阻尼器均匀布置比集中布置能更好地控制悬挂楼面的相对位移。     

墙式连接金属阻尼器RC框架振动台试验研究

为研究金属阻尼器墙式连接方式的有效性,检验金属阻尼器对RC框架的减震效果,设计并制作1/4缩尺的4层无控结构(纯框架)和减震结构(设置金属阻尼器)振动台试验模型.选取一条人工合成地震动和Takatori天然地震动,调幅到不同地震动强度进行振动台试验,对模型结构动力特性(自振频率、阻尼比)和结构响应(位移、加速度、剪力)...