塔式容器结构抗震设计的动力可靠性研究

本文运用随机有限元原理提供了结构系统在地震力作用下的可靠性分析方法，并运用该方法对现行规范抗震设计的几种典型塔式容顺进行动力可靠性研究，其结果可为制订塔式容器结构抗震可靠性设计标准作为参考。     

结构抗震性能评估的动测方法研究

本文通过对工程结构，特别是高层建筑的动力特性参数的现场实测，结合已有的室内、室外强度、抗震承载力实验结果，为工程结构抗震性能及使用安全性的判定提供一套简便实用的方法，继而为震害预测、抗震设计、抗震加固、房屋安全鉴定等提供较客观的依据。     

钢管混凝土结构抗震性能的比较研究

分别对钢管混凝土柱及钢盘混凝土柱的5层框架结构进行了抗城性能对比试验研究，从理论上分析比较了两种结构的动力特性、多种地震波输入下的结构加速度反应和位移反应，综合评定了钢管混凝土结构的抗城性能。为该类结构的设计提供了参考数据。     

高耸塔结构动力特性的监测与分析

使用适合于高柔结构的测试系统和测试技术,监测了塔,陕西塔和天津塔在环境振动激励下不同高程的加速度反应,使用在ＭＡＴＬＡＢ语言环境下编制的数据处理,分析,模态识别程序在微机上对各测点输出信号进行了处理,分析,识别得出３座塔结构平动前１０阶模态频率和前３阶模态阻尼比。     

石结构抗震可靠度的分析与应用

在文献［１］的基础上进一步探讨了石结构体系抗震动力反应分析的计算方法，给出了场地地震条件下结构在使用期间内抗震可靠度的应用实例。定量分析的结果表明，严格地控制结构高度、层数和砂浆强度等级等指标，是提高多层石结构抗震能力的有效措施。     

结构抗震设计时程分析法的分析研究

文章回顾了我国抗震设计规范的演变过程,将时程分析法与底部剪力法和振型分解反应谱法进行了对比,指出了时程分析法在抗震设计计算中的地位与作用,时程分析法是能够考虑地震动三要素、地震环境、结构的非线性和能量损耗及损伤的真正动力分析方法,是比底部剪力法和振型分解反应谱法更精确、更可靠、更合理的方法,不应仅仅作为补充计算的方法,...     

5跨连续中承式钢管混凝土拱桥抗震性能分析

钢管混凝土拱桥由于桥型优美在城市桥梁中得到广泛应用,对某正在设计的5跨连续巾承式钢管混凝土拱桥进行了动力特性和抗震性能分析,根据该桥的结构特点,建立了’该桥的空间有限元分析模型,计算桥梁的自振特性,基于反应谱方法计算了该桥在横向、纵向水平地震反应,计算结果表明：该桥拱肋的面外刚度相对较小,在桥梁振动中首先出现拱肋的面外振动;桥梁的竖向振动表现为拱肋与桥面的整体竖向振动,其基频明显比拱肋面外振动大;主拱肋的轴力由横桥向地震动控制,其他内力由纵桥向地震动控制;地震作用对弯矩的影响较大,故主拱的内力计算应考虑地震力的影响;在设计计算中除常规关键点应作为控制点外,内外拱连接处也应作为控制点。计算结果已为该桥的抗震设计提供了参考。     

Applicability of pushover methods for the seismic analysis of single‐column bent viaducts

An overview of the applicability of a typical single‐mode pushover method (the N2 method) and two typical multi‐mode pushover methods (the modal pushover analysis (MPA) and incremental response spectrum analysis (IRSA) methods) for the analysis of single column bent viaducts in the transverse direction is presented. Previous research, which was limited to relatively short viaducts supported by few columns, has been extended to longer viaducts with more bents. The single‐mode N2 method is accurate enough for bridges where the effective modal mass of the fundamental mode is at least 80% of the total mass. The applicability of this method depends on (a) the ratio of the stiffness of the superstructure to that of the bents and (b) the strength of the bents. In short bridges with few columns, the accuracy of the N2 method increases as the seismic intensity increases, whereas in long viaducts (e.g. viaducts with lengths greater than 500 m) the method is in general less effective. In the case of the analyzed moderately irregular long viaducts, which are common in construction design practice, the MPA method performed well. For the analysis of bridges where the modes change significantly, depending on the seismic intensity, the IRSA method is in principle more appropriate, unless a viaduct is torsionally sensitive. In such cases, all simplified methods should be used with care. Copyright © 2008 John Wiley & Sons, Ltd.     

城市高架桥合理抗震体系选择与经济性对比

探讨了基于两水准设防的城市高架桥的合理抗震设防标准与相应的结构性能目标.选取两座典型的城市高架桥结构,包括一座正线桥和一座匝道桥,分别采用延性抗震体系和减、隔震体系进行结构抗震设计.对比了不同结构抗震体系所对应的结构在各水准地震作用下具体抗震性能表现,结果表明减、隔震体系具有更优的抗震性能.在此基础上,进一步从经济性的...     

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。     

城市轨道交通U型梁动力性能研究与实验验证

为探讨城市轨道交通U型梁车桥系统的动力响应,采用线性化轮轨模型建立了31个自由度的轮轨式车辆动力学模型.模型考虑了新型算法的横竖向轨道不平顺,以重庆市轨道交通一号线工程中梁山以西高架区间所采用标准跨径为30m的单线小U结构为对象,采用自编程序对机车车辆过桥时的车桥耦合振动进行了分析,并通过计算与实测结果的对比分析对所建...     

The model of double bounds of stochastic stress in seismic risk analysis of faults

In this paper, the major idea is: when seismic stress accumulates to a certain extent, a stick slip earthquake will occur on the fault plane. The seismic stress before and after the stick slip earthquake occurrence are both stochastic variables. According to this idea, the model of double bounds of stochastic stress is proposed, and also it is used to analyse the seismic risk of Xian Shui River Fault Zone in the coming 30 years, the result is similar to what the Seismological Bureau of Sichuan Province has predicted. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 477–483, 1993.     

高层建筑结构抗震设计中鞭梢效应的分析

将钢筋混凝土结构离散为能模拟梁、柱、墙抗震性能的单元，采用串并联刚片系振动模型，体现空间各构件的协同工作，采用改进的Wilson-θ法。对鞭梢效应在高层建筑结构抗震中的影响作详细分析，做到合理利用鞭梢效应，从而可以解决高层建筑物中层间位移起决定性作用的问题，达到合理、经济的效果。     

基于能量被动耗能结构抗震设计方法的研究

将结构前两阶振型各自等效为单自由度,采用模态pushover分析确定各等效单自由度的屈服强度系数和延性系数,然后由反应谱计算各阶振型耗散能量需求,利用各振型能量分布曲线,求得各层耗散能量需求,叠加得到各层地震总能量需求,据此确定耗能装置的类型及设计参数.运用该方法对9层钢框架进行了设计,并通过非线性动力分析进行了验证,结果表明该方法精确度符合实际工程需求.     

Study of the seismic performance of expansion double spherical seismic isolation bearings for continuous girder bridges

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 ...     

Shake table testing on restoring capability of double concave friction pendulum seismic isolation systems

After an earthquake, non‐negligible residual displacements may affect the serviceability of a base isolated structure, if the isolation system does not possess a good restoring capability. The permanent offset does not affect the performance unless the design is problematic for utilities, also considering possible concerns related to the maintenance of the devices. Starting from experimental and analytical results of previous studies, the restoring capability of Double Concave Friction Pendulum bearings is investigated in this paper. A simplified design suggestion for the estimation of maximum expected residual displacements for currently used friction pendulum systems is then validated. The study is based on controlled‐displacement and seismic input experiments, both performed under unidirectional motion. Several shaking table tests have been carried out on a three‐dimensional isolated specimen structure. The same sequence of seismic inputs was applied considering three different conditions of sliding surfaces corresponding to low, medium and high friction. The accumulation of residual displacements is also investigated by means of nonlinear dynamic analysis. Copyright © 2017 John Wiley & Sons, Ltd.