弦支穹顶结构动力反应分析   总被引：1，自引：0，他引：1  

张增军  马人乐  张哲 《世界地震工程》2006,22(4):89-94

以天津开发区商务中心大堂的弦支穹顶为研究对象,分析了弦支穹顶结构体系的自振特性,分别运用随机模拟风振分析方法和时间历程分析方法,对其进行了风振和地震反应分析,得到了结构在动力荷载作用下的响应时程,并对分析结果进行了频谱分析和统计分析。研究发现弦支穹顶结构的自振频率呈密集型分布,且振型复杂;结构的风振响应基本以受迫振动为主,没有出现明显的峰值共振现象;结构的地震响应在前几阶基频处出现了较为明显的峰值共振现象;从振动的幅值角度看,风荷载的动力作用效应相对于地震荷载要显著。  相似文献   

单桩水平及水平-摇摆耦合振动分析   总被引：1，自引：0，他引：1  

李耀庄  李博 《世界地震工程》2006,22(4):160-165

采用Novak薄层法,分析了单桩的水平及水平-摇摆耦合振动。然后,引进Novak和韩英才的边界层理论,全面分析和对比了匀质弹性、匀质粘弹性和非匀质粘弹性地基中单桩的动力阻抗,考察了各种因素对单桩动力阻抗的影响程度。在推导单桩水平动力阻抗的过程中,采用克雷洛夫函数和初参数法求解单桩的水平振动微分方程,从而能够方便地考虑桩长和桩底土对单桩动力阻抗的影响。计算表明,当桩的长径比较小时,桩底土对单桩动力阻抗有重要的影响。  相似文献   

连续梁桥中设置粘弹性阻尼器的减震效果分析          下载免费PDF全文

李兴田  朱东生 《地震工程学报》2006,28(1):26-30

研究了设有粘弹性阻尼器的连续梁桥的地震反应,探讨了阻尼器在连续梁桥中的减震效果及阻尼器参数对减震效果的影响。结果表明:阻尼器对桥梁结构具有减震效果,要达到良好的减震效果必须对阻尼器的参数加以优化。  相似文献   

三维层状地基空沟主动隔振分析   总被引：3，自引：2，他引：3       下载免费PDF全文

高广运  彭争光  李伟  冯世进 《地震工程学报》2006,28(3):210-215,220

基于薄层法在研究层状介质中波的传播问题的高效性、边界单元法处理无限域问题的精确性,结合二者的优点提出三维层状地基薄层法基本解答,建立了基于三维层状半空间薄层法位移基本解答的半解析动力边界元法。该方法可有效的分析多层场地的动力问题,解决土-结构动力相互作用问题。同时分别对粘弹性上软下硬地基及上硬下软地基的三维空沟主动隔振进行了详细的分析。结果表明,两种情况下采用空沟屏障隔振均可以取得一定的隔振效果;同时,地基分层参数对空沟隔振体系的隔振效果影响显著。  相似文献   

Dynamic performance of cable-stayed bridge tower with multi-stage pendulum mass damper under wind excitations—Ⅱ: Experiment   总被引：1，自引：0，他引：1  

郭安薪  徐幼麟  李惠 《地震工程与工程振动(英文版)》2007,(4)

The possibility of using a multi-stage pendulum mass damper (MSPMD) to control wind-induced vibration of a single column tower of a cable-stayed bridge during construction was studied theoretically in part I of this work. In this paper, the performance of the MSPMD for reducing bridge tower vibration is studied experimentally. A MSPMD model and a tower model of the bridge with geometry scaling of 1:100 were designed and manufactured. Calibration of the MSPMD model with different wire lengths is conducted to verify the analytical model of the damper. A series of tests for the uncontrolled freestanding tower, tower with cables, and tower with MSPMD model are then performed under harmonic and white noise excitations. The experimental results show that the responses of the tower model signif icantly decrease with the installation of the MSPMD model, which demonstrates the effectiveness of the MSPMD to mitigate the vibration of the bridge tower.  相似文献   

强非线性杜芬系统随机振动的等效化研究     

樊友景  石志晓  李大望 《世界地震工程》2007,23(3):29-31

以相对穿阈率为评估指标，探讨了强非线性杜芬系统稳态随机振动的等效化问题。结果表明，在不同位移阈值条件下，随着系统振动非线性的增强，立方恢复力等效模型预测精度逐步提高。该等效模型对强非线性杜芬系统具有良好的适用性。  相似文献   

基于动力可靠度的隔震结构参数模糊优化   总被引：1，自引：0，他引：1  

杜永峰  白莉  李慧  张丽娟 《世界地震工程》2007,23(3):60-67

分别选取Bouc—Wen和退化Bouc—Wen模型描述隔震层及上部结构滞变回复力，采用虚拟激励法进行隔震结构随机响应分析。用各层最大层间位移响应和累计疲劳损伤指数建立双参数的功能状态方程，用一次二阶矩理论计算隔震结构失效概率。选用一个隔震框架作为数值算例，探讨了低频过滤器、隔震阻尼比和隔震刚度对隔震结构各子系统条件失效概率的影响。建立了隔震结构参数多目标优化模型，用失效概率确定单因素评判的隶属度，并采用最大隶属度法对隔震参数进行模糊优化。  相似文献   

郑州大学体育馆钢屋盖动力特性分析   总被引：1，自引：0，他引：1  

童丽萍  胡振中  冯志杰 《世界地震工程》2006,22(1):84-88

以郑州大学新校区体育馆钢屋盖为研究对象,采用ANSYS分析程序,建立了钢屋盖空间结构计算模型,利用子空间迭代法计算自振周期和振型,从而得到钢屋盖动力特性,为进一步研究该结构的动力响应打下基础。  相似文献   

Cone model for two surface foundations on layered soil     

陈文化 《地震工程与工程振动(英文版)》2006,5(2):183-187

In this paper, the cone model is applied to the vibration analysis of two foundations on a layered soil half space. In the analysis, the total stress field in the subsoil is divided into the free-field and the scattering field. Seed＇s simplified method is adopted for the free-field analysis, while the cone model is proposed for analyzing the dynamic scattering stress wave field. The shear stress field and the compressive stress field in the layered stratum with two scattering sources are calculated by shear cone and compressive cone, respectively. Furthermore, the stress fields in the subsoil with two foundations are divided into six zones, and the P wave and S wave are analyzed in each zone. Numerical results are provided to illustrate features of the added stress field for two surface foundations under vertical and horizontal sinusoidal force excitation. The proposed cone model may be useful in handling some of the complex problems associated with multi-scattering sources.  相似文献   

Propagation of non-stationary random waves in viscoelastic stratified solids     

Q. Gao  J.H. Lin  W.X. Zhong  F.W. Williams   《Computers and Geotechnics》2006,33(8):444-453

This paper covers propagation of non-stationary random waves in stratified materials. The layered solid considered is located above the bedrock, whose material properties are assumed to be much stiffer than the solid, and known power spectrum densities of the non-stationary random excitations are input at the bedrock. The governing differential equations are derived in the frequency and wavenumber domain and the response power spectrum densities of the ground are investigated. The solution method presented uses the pseudo-excitation method in combination with the precise integration method and the extended Wittrick–Williams algorithm. The examples have up to three layers.  相似文献