基础隔震高层建筑地震响应的理论分析

本文对某高层隔震框架－剪力墙结构的三维地震响应进行了有限元分析计算，对比了隔震结构及其相应非隔震结构的动力特性，给出了在多遇地震和罕遇地震作用下结构的最大层间剪力，层间位移等，得到一些有意义的结论。     

基于GIS的城市建筑群动力响应分析模型建模方法研究

建筑群震害响应模拟是现代城市震害防御管理工作的基础。高效的建筑信息获取方法与科学合理的建筑群动力响应分析模型建模方法是快速、准确震害模拟的前提,也是震害防御科学管理、迅速决策和精准施策的必要保障。本文提出利用GIS平台进行矢量地图数据采集、多图层空间叠加分析及地形分析;结合我国各地市政府数据开放平台,获取建筑使用功能、建成年代、结构类型及场地类别等基本信息;在此基础上建立一套基于真实城市信息的建筑群动力响应分析模型建模方法。该方法操作简便、模型精度高并且建模速度快,可实现城市区域大规模建筑群高效建模。针对成都市某街区建筑群进行数据采集和模型建立,验证了该方法的可行性和有效性。     

Optimal design of tuned mass dampers for a multi‐storey cross laminated timber building against seismic loads

In this paper, the effectiveness of different design solutions for tuned mass dampers (TMD) applied to high‐rise cross‐laminated (X‐Lam) timber buildings as a means to reduce the seismic accelerations was investigated. A seven‐storey full‐scale structure previously tested on shaking table was used as a reference. The optimal design parameters of the TMDs, i.e. damping and frequency ratios, were determined by using a genetic algorithm on a simplified model of the reference structure, composed by seven masses each representing one storey. The optimal solutions for the TMDs were then applied to a detailed finite element model of the seven‐storey building, where the timber panels were modelled with shell elements and the steel connectors with linear spring. By comparing the numerical results of the building with and without multiple TMDs, the improvement in seismic response was assessed. Dynamic time‐history analyses were carried out for a set of seven natural records, selected in accordance with Eurocode 8, on the simplified model, and for Kobe earthquake ground motion on the detailed model. Results in terms of acceleration reduction for different TMD configurations show that the behaviour of the seven‐storey timber building can be significantly improved, especially at the upper storeys. Copyright © 2016 John Wiley & Sons, Ltd.     

Experimental study on multiple tuned mass dampers to reduce seismic responses of a three‐storey building structure

In this study, several mass dampers were designed and fabricated to suppress the seismic responses of a ¼‐scale three‐storey building structure. The dynamic properties of the dampers and structure were identified from free and forced vibration tests. The building structure with or without the dampers was, respectively, tested on a shake table under the white noise excitation, the scaled 1940 El Centro earthquake and the scaled 1952 Taft earthquake. The dampers were placed on the building floors using the sequential procedure developed by the authors in previous studies. Experimental results indicated that the multiple damper system is substantially superior to a single tuned mass damper in mitigating the floor accelerations even though the multiple dampers are sub‐optimal in terms of tuning frequency, damping and placement. These results validated the sequential procedure for placement of the multiple dampers. The structure was also analysed numerically based on the shake table excitation and the identified structure and damper parameters for all test cases. Numerical and experimental results are in good agreement, validating the dynamic properties identified. Copyright © 2003 John Wiley & Sons, Ltd.     

高层隔震建筑三维地震响应

对某高层框架－筒体结构进行了三维有限元时程分析，考虑了基础夹层橡胶了隔震垫的弹塑性特性和粘滞阻尼，分析了结构在地震波作用下的动力响应，为高层建筑中推广应用基础隔震技术提供了理论依据。     

建筑结构地震响应半主动控制的遗传-模糊算法

本文针对建筑结构地震响应半主动控制问题,应用基于遗传算法优化模糊规则库的遗传—模糊控制方法,通过MR阻尼器实现减小建筑结构地震响应。将结构的位移和加速度响应峰值控制双重指标作为目标函数,运用遗传算法的基本操作得到一组优化的模糊推理规则。以结构位移、加速度、地震加速度信号作为输入量,以MR阻尼器所提供的控制力为输出量,分别构造单阻尼器和多阻尼器的模糊控制策略。以某3层和6层框架结构为例,分别对两种遗传—模糊控制算法进行数值仿真分析,并与LQR最优控制结果进行比较。数值分析结果表明,采用遗传—模糊算法能够有效地减小结构的地震响应。     

Evaluation of combination rules for maximum response calculation in multicomponent seismic analysis

The existing rules for combining peak response to individual components of ground motion are evaluated. The response values r_e to two horizontal components of ground motion estimated by four multicomponent combination rules—SRSS‐, 30%‐, 40%‐ and simplified‐SRSS‐rules—are compared with the critical response, r_cr, obtained by the CQC3‐rule, which takes into account the direction of the principal ground components with respect to the structural axes and provides the largest response over all possible seismic incident angles. The following results are obtained in the first part of the paper and are valid for any elastic structure and any earthquake design response spectrum: For realistic values of the ratio γ of the design spectra for the two principal components of ground motion the SRSS‐rule estimate lies between 0.79r_cr and 1.00r_cr, the Simplified‐SRSS‐rule estimate lies between 1.00r_cr and 1.26r_cr, the 40%‐rule estimate lies between 0.99r_cr and 1.25r_cr, and the 30%‐rule estimate lies between 0.92r_cr and 1.16r_cr. None of the multicomponent combination rules account for the increase in response of systems if the vibration periods of the two modes that contribute most to the response to the x‐ and y‐components of ground motion are close to each other. Evaluated in the second part of the paper is the accuracy of the multicomponent combination rules in estimating the response of a range of one‐storey systems with (a) symmetrical plan and (b) unsymmetrical plan, and of two multistorey buildings. The SRSS‐rule underestimates the response by up to 16% and the other three rules overestimate it by up to 18%. Although these errors appear to be smaller than the many approximations inherent in structural design, they can be eliminated with very little additional computation by using an explicit formula for the critical response based on the CQC3 rule. Copyright © 2001 John Wiley & Sons, Ltd.     

Optimized earthquake response of multi‐storey buildings with seismic isolation at various elevations

The response of multi‐storey structures can be controlled under earthquake actions by installing seismic isolators at various storey levels. By vertically distributing isolation devices at various elevations, the designer is provided with numerous options to appropriately adjust the seismic performance of a building. However, introducing seismic isolators at various storey levels is not a straightforward task, as it may lead to favourable or unfavourable structural behaviour depending on a large number of factors. As a consequence, a rather chaotic decision space of seismic isolation configurations arises, within which a favourable solution needs to be located. The search for favourable isolators' configurations is formulated in this work as a single‐objective optimization task. The aim of the optimization process is to minimize the maximum floor acceleration of the building under consideration, while constraints are specified to control the maximum interstorey drift, the maximum base displacement and the total seismic isolation cost. A genetic algorithm is implemented to perform this optimization task, which selectively introduces seismic isolators at various elevations, in order to identify the optimal configuration for the isolators satisfying the pre‐specified constraints. This way, optimized earthquake response of multi‐storey buildings can be obtained. The effectiveness of the proposed optimization procedure in the design of a seismically isolated structure is demonstrated in a numerical study using time‐history analyses of a typical six‐storey building. Copyright © 2012 John Wiley & Sons, Ltd.     

群体建筑物地震破坏概率模型研究

提出了一种通过构建具有普适性的概率模型对群体建筑物进行震害预测的方法。该方法基于已有的群体建筑物易损性矩阵,通过概率分析和数据拟合,进行构建建筑群的破坏概率模型,并通过计算建筑物易损性指数的均值和方差来确定其具体参数。分析表明,该概率模型对群体建筑物震害预测具有一定的可行性和普遍的适用性。     

Active control of building seismic response by energy dissipation

Active energy dissipation is proved to be very effective for abating seismic effects on buildings. The implementation of this concept in seismic design of buildings is studied by response simulations of a single storey building subjected to earthquake motion. Active energy dissipaters can be installed as part of the building lateral load bracing, and they regulate the strength and stiffness of the bracing during the building's response to the seismic events. The energy is dissipated when the bracing load exceeds the axial strength provided by the dissipater, and the bracing telescopes in and out. The design parameters of active energy dissipaters are described using the simulated response of a single storey building to ground pulse and harmonic ground excitation. The feasibility of the energy dissipater is demonstrated by the development and construction of a full-scale prototype device called an Active Slip Bracing Device (ASBD). The device utilizes Coulomb friction. The active characteristics are implemented by a computer controlled clamping mechanism on the friction interface. The ASBD's control of the strength and stiffness is investigated.     

Actual seismic response controlled building with semi-active damper system

This paper presents the first application of a semi-active damper system to an actual building. The Semi-active Hydraulic Damper (SHD) can produce a maximum damping force of 1000 kN with an electric power of 70 W. It is compact, so a large number of them can be installed in a single building. It is thus possible to control the building's response during a severe earthquake, because a large control force is obtained in comparison with a conventional active control system. This paper outlines the building, the control system configuration, the SHD, the control method using a Linear Quadratic Regulator, the response analysis results of the controlled building, and the dynamic loading test results of the actual SHD. The simulation analysis shows that damage to buildings can be prevented in a severe earthquake by SHD control. The dynamic loading test results of the SHD are reported, which show that the specified design values were obtained in the basic characteristic test. The control performance test using simulated response time histories, also shows that the damping force agrees well with the command. Finally, it is confirmed that the semi-active damper system applied to an actual building effectively controls its response in severe earthquakes. Copyright © 1999 John Wiley & Sons Ltd.     

A neural network approach for structural identification and diagnosis of a building from seismic response data

This work presents a novel procedure for identifying the dynamic characteristics of a building and diagnosing whether the building has been damaged by earthquakes, using a back‐propagation neural network approach. The dynamic characteristics are directly evaluated from the weighting matrices of the neural network trained by observed acceleration responses and input base excitations. Whether the building is damaged under a large earthquake is assessed by comparing the modal parameters and responses for this large earthquake with those for a small earthquake that has not caused this building any damage. The feasibility of the approach is demonstrated through processing the dynamic responses of a five‐storey steel frame, subjected to different strengths of the Kobe earthquake, in shaking table tests. Copyright © 2002 John Wiley & Sons, Ltd.     

对称结构在水平地震作用下的扭转效应和抗扭设计探讨

针对水平地震作用下对称结构抗扭设计中存在的问题,分析了对称结构扭转振动的原因,然后分别采用静力和动力方法研究了考虑偶然偏心作用时结构反应的增大效应,比较了这两种方法计算结果的异同,最后结合我国抗震规范提出了适当的结论和改进建议,为对称结构的抗扭设计提供了理论依据。     

Understanding and predicting effects of supplemental viscous damping on seismic response of asymmetric one‐storey systems

Supplemental damping could mitigate the earthquake‐induced damage in buildings with asymmetric plan, known to be more vulnerable to damage than comparable symmetric‐plan buildings. This investigation aims to improve the understanding of how and why planwise distribution of fluid viscous dampers (FVDs) influences the response of linearly elastic, one‐storey, asymmetric‐plan systems. Starting with vibration mode shapes, we predict this influence on the modal damping ratios, and in turn on the individual modal responses and the total response. These predictions are confirmed by the computed responses, which demonstrated that the reduction in earthquake response of the system achieved by supplemental damping is strongly influenced by its planwise distribution, which is characterized by four parameters. Identified are asymmetric distributions of supplemental damping that are more effective in reducing the response compared to symmetric distribution. The percentage reduction achieved by a judiciously selected asymmetric distribution can be twice or even larger compared to symmetric distribution. Copyright © 2001 John Wiley & Sons, Ltd.     

单层柱面网壳弹塑性地震反应特征

本文对网壳结构的弹塑性抗震性能进行了探讨。根据结构弹性有限元理论，结合网壳结构受力特点，推导出网壳结构单元的弹塑性矩阵表达式。然后对单层柱面网壳结构的弹塑性地震反应进行了具体分析，给出了节点位移和杆件应力变化规律，并讨论了矢跨比变化对网壳弹塑性性能的影响，从而揭示出这类网壳的弹塑性地震反应特点。     

Higher order model for the seismic response of bridge embankments

The paper presents a new higher order model for the dynamic analysis of embankments. By considering a Legendre polynomial expansion to describe the motion at a generic point of the embankment, the application of the Lagrange-D’Alembert principle in conjunction with a through-the-width closed-form integration allows reducing the 3D physical domain into a 2D analytical domain. 4-node isoparametric elements with linear interpolating functions are used to numerically solve the problem. The model is suitable for bridge embankments by introducing a kinematic rigid constraint to account for the presence of the abutment. The embankment frequency dependent impedances and the displacements to be imposed to the abutment in bridge seismic analyses are obtained by condensation. The model has been validated comparing results with those furnished by high-fidelity 3D finite element models. The application to the approach embankment of an instrumented bridge subjected to a severe earthquake has demonstrated the model capability to capture both occurrence and intensity of main response peaks, as well as the frequency content of the response.     

Passive seismic response controlled high-rise building with high damping device

This paper describes a feasibility study on a high-damping device (HiDAM) installed in a building structure by way of a bracing mechanism. A seismic response analysis with respect to a high-rise building approximately 100 m high is reported. Proper adjustment of the damping coefficient of the HiDAM (oil damper) provided an over all damping factor of about 10–20 per cent to the building structure, and reductions in the response, deformation and shear forces were verified analytically. This paper reports also the performance confirmation tests conducted on a model device of the HiDAM which satisfied the specifications determined from the analytical results. The test results demonstrate the feasibility of the HiDAM and the possibility of utilizing it in high-rise buildings.     

地震物理模型材料研制与应用研究

地震物理模型试验的基础是地震物理模型的建造,其中设计适当的配方,调配出所需要的模型速度是模型建造的关键.本文根据互穿网络和共聚网络聚合物改性方法的原理,研究了环氧树脂、橡胶类等高分子材料的互穿网络和共聚网络过程,并按照地震物理模拟对模型材料的要求,实现了不同材料的共混,改善了固化后共聚物的交联度.讨论和分析了影响地震物理模型建造的各种因素,并从模型材料选择、配方调整等方面提出了相应的解决办法,降低了固化反应放热峰的温度、调整了固化放热的速度、降低了固化时的收缩率和线膨胀系数,使固化物具有较高的热稳定性和较好的力学性能.建立了比较完备的、从低到高的材料速度系列.通过实例验证了本文方法的有效性,模型材料的适用性.     

采用摩擦垫层及阻尼器对外套加层结构体系的减振研究

本文提出了一种耗能减震加层结构新体系,即利用旧有建筑顶层与加层结构之间的摩擦垫层井依靠在两结构各层连接点处增设的耗能阻尼器来吸收耗散能量的减振体系。在进行非线性动力分析过程中,首次建立了系统的结构模型,引入了一种新的库仑摩擦力表达式并对影响体系减振率的有关参数进行了研究。最后通过对一实际工程的设计和计算,验证了这种加层减振做法的有效性。