首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 703 毫秒
1.
目的是建立5种被动的动力减振器对长宽比较大的高层建筑侧移-扭转脉动风振反应控制优化设计的统一方法。文中,在建立了5种被动动力减振器对高层建筑侧移-扭转脉动风振反应控制统一的方程的基础上,导出了被动动力减振器对高层建筑侧移-扭转脉动风振反应控制效果最优等效阻尼比和被动动力减振器最优设计参数的基本公式。通过工程实例的计算与分析,本文比较了5种被动动力减振器对高层建筑侧移-扭转脉动风振反应的控制效果,讨论了动力减振器在楼层上设置位置对动力减振器最优设计参数和控制效果的影响,得到了2个有工程价值的重要结论。  相似文献   

2.
钢筋混凝土剪力墙扭转行为的试验研究   总被引:1,自引:0,他引:1  
通过对4个1/2缩尺的钢筋混凝土剪力墙的静力加载试验,探讨了不同截面尺寸及配筋率对剪力墙抗扭强度、扭转变形、破坏形态及裂缝发展的影响.试验揭示了三种扭转破坏形态:少筋破坏、部分超筋破坏及超筋破坏.通过理论值与实验值的比较发现,斜弯理论(经PCA①验修正)能够很好的预测墙的开裂扭矩及开裂扭转角.另外,通过对试验所得的全变形曲线与软化桁架模型(Soflened Truss Model)的预测变形曲线进行比较,发现基于梁单元扭转机理的软化桁架模型可以较合理地预测墙的最大扭转值及对应的扭转角,但不能较好地模拟实验曲线中的下降段.  相似文献   

3.
对分层弹性地基中的单桩基础通过特性分析建立了合理的力学模型,按分层弹性地基土模型对柱进行了扭转振动分析,给出了桩基础扭转自振特征及在扭转地震载荷与扭转振动载荷作用下的强迫反应解析解,文中的解析公式为分层弹性地基中的桩基础扭转动力反应分析提供了一种新的解析方法。  相似文献   

4.
采用定参理想集总参数计算体系,以动力基础非线性动力学模型和非线性广义刚度函数的概念为基础,将动力基础模型从竖向非线性振动推广至水平非线性振动、扭转非线性振动以及水平-回转二自由度耦合非线性振动和竖向-水平-回转三自由度非线性耦合振动,建立了动力基础非线性动力学模型的一般表达式,为动力基础非线性设计提供了理论。  相似文献   

5.
本文对场地土按分层弹性地基土建立了合理的力学模型,通过动力分析,给出了分层弹性地基场地土扭转自振特性及在扭转地震载荷作用下强迫反应的解析解,文中的解析公式为分层弹性的基场地土扭转地震反应分析提供了一种新的解析方法.  相似文献   

6.
多层偏心结构非线性地震反应分析   总被引:1,自引:1,他引:1  
本文利用层单元模型,建立了基于层剪力-扭矩等效屈服EYST面概念的求解多层偏心结构体系双水平向地震动作用下平扭耦联非线性地震反应的简化算法,并讨论了控制偏心结构非线性扭转反应的相关结构参数;通过数值分析,初步验证了该简化方法的实用性和可靠性。  相似文献   

7.
研究了非对称结构扭转振动多重调谐质量阻尼器(MTMD)控制的最优位置。本文采用的MTMD具有相同的刚度、阻尼,但质量不同。基于导出的设置MTMD时非对称结构扭转角位移传递函数,建立了扭转角位移动力放大系数解析式。MTMD最优参数的评价准则定义为:非对称结构最大扭转角位移动力放大系数的最小值的最小化。MTMD的有效性评价准则定义为:非对称结构最大扭转角位移动力放大系数的最小值的最小化与未设置MTMD时非对称结构最大扭转角位移动力放大系数的比值。基于定义的评价准则,研究了非对称结构的标准化偏心系数(NER)和扭转对侧向频率比(TTFR)对不同位置MTMD最优参数和有效性的影响。  相似文献   

8.
给出了弹性半空间表面刚性矩形基础水平、竖向、摇摆和扭转方向阻抗函数一种近似公式。利用这种近似公式,可以得到已知长宽比和泊松比矩形基础的阻抗函数频域解,而且还可以直接得到阻抗函数的等效时域集中参数模型。  相似文献   

9.
某高层建筑结构模型振动台试验研究及有限元分析   总被引:10,自引:2,他引:8  
本文对于复杂体型高层建筑结构在地震作用下的动力特性与反应,从模型振动台试验和有限元计算两方面进行了研究。对一个1:50比例的高层建筑模进行了振动台模型地震试验,根据试验结果。通过相似关系得到原型结构在地震作用下的动力特性与反应。  相似文献   

10.
利用有限单元法,基于力学原理和几何协调条件,导出了非对称箱型截面梁单元的弯扭耦合刚度矩阵,建立了斜拉桥在车辆荷载作用下的横向动力分析模型。由于考虑了箱梁的约束扭转,该模型能够分析复线或多线铁路桥在偏载作用下的横向振动问题。以桥梁轨道随机不平顺作为激振源,进行了机车过桥的实例分析。计算结果表明,桥梁的车激横向动力响应随车速及轨道不平顺样本的不同而变化,并随桥跨的增加而快速变得显著,车辆偏载对箱梁扭转振动有显著影响,所建立的力学模型是斜拉桥车桥耦合振动分析的实用模型。  相似文献   

11.
在大气边界层风洞进行了"珠江城"商务写字楼大比例尺(1:150)模型风洞试验,通过对风洞试验数据分析,获得了基础等效静风荷载及结构顶部风致加速度响应。并将其结果与其它较小比例尺的两个风洞试验结果相对比,分析了模型几何缩尺比、周边建筑及平均风剖面对试验结果的影响。获得的结果可以为此结构设计提供风荷载,同时也为其他建筑的抗风设计和风洞实验提供技术参考。  相似文献   

12.
High buildings or architectural complex in urban areas remarkably distort the urban surface wind fields. As the air flow approaches,local strong wind may appear around the buildings. The strong wind makes the pedestrians on sidewalks, entrances and terrace very uncomfortable and causes the pedestrian level wind environment problem. In this studies, hot-wire wind measurement, wind scouring in wind tunnel and numerical computation were carried out to evaluate the wind environment of tall buildings in the prevailing flow conditions in Beijing areas. The results obtained by three techniques were compared and mutually verified. The conclusions drawn from three approaches agree with each other. Also the advantages and limitations of each method were analyzed. It is suggested that the combination of different techniques may produce better assessment of wind environment around high buildings.  相似文献   

13.
The response of base-isolated buildings to gusting wind is analysed theoretically based on experimental data obtained in a boundary layer wind tunnel. A comparison is made with the response evaluated using existing codes. A special procedure, similar to that of current codes, for computing the alongwind and torsional responses of base-isolated buildings is presented.  相似文献   

14.
For super high-rise buildings,the vibration period of the basic mode is several seconds,and it is very close to the period of the fluctuating wind.The damping of super high-rise buildings is low,so super high-rise buildings are very sensitive to fluctuating wind.The wind load is one of the key loads in the design of super high-rise buildings.It is known that only the basic mode is needed in the wind-response analysis of tall buildings.However,for super high-rise buildings,especially for the acceleration response,because of the frequency amplification of the high modes,the high modes and the mode coupling may need to be considered.Three typical super high-rise projects with the SMPSS in wind tunnel tests and the random vibration theory method were used to analyze the effect of high modes on the wind-induced response.The conclusions can be drawn as follows.First,for the displacement response,the basic mode is dominant,and the high modes can be neglected.Second,for the acceleration response,the high modes and the mode coupling should be considered.Lastly,the strain energy of modes can only give the vibration energy distribution of the high-rise building,and it cannot describe the local wind-induced vibration of high-rise buildings,especially for the top acceleration response.  相似文献   

15.
Flow structure and wind pressure distribution caused by obtuse obstacles are usually the focuses in Computational Wind Engineer researches (CWE). By solving the non-hydrostatical dynamic equations, PUMA model (Peking University Model of Atmospheric Environment) was developed and applied to simulating the flow structure and wind pressure distribution around a tower-shaped building. Evaluation about the wind environment and wind loads around the building was obtained through the analysis of the numerical simulation results and wind tunnel data. Comparisons between the simulation and wind tunnel study indicate that numerical simulation results agree well in the flow field and wind pressure distribution around the tower-shaped building. On the other hand, the horizontal grid interval of 2 m and the vertical grid of 3 m were still too crude to simulate the flow structure and wind pressure distribution on the building surface more exactly in detail; and the absence of suitable pressure perturbation parameterization scheme between the solid and the adjacent space also limits the accuracy of the numerical simulation. The numerical simulation model can be used to evaluate the wind environment and wind load around high buildings.  相似文献   

16.
As high‐rise buildings are built taller and more slender, their dynamic behavior becomes an increasingly critical design consideration. Wind‐induced vibrations cause an increase in the lateral wind design loads, but more importantly, they can be perceived by building occupants, creating levels of discomfort ranging from minor annoyance to severe motion sickness. The current techniques to address wind vibration perception include stiffening the lateral load‐resisting system, adding mass to the building, reducing the number of stories, or incorporating a vibration absorber at the top of the building; each solution has significant economic consequences for builders. Significant distributed damage is also expected in tall buildings under severe seismic loading, as a result of the ductile seismic design philosophy that is widely used for such structures. In this paper, the viscoelastic coupling damper (VCD) that was developed at the University of Toronto to increase the level of inherent damping of tall coupled shear wall buildings to control wind‐induced and earthquake‐induced dynamic vibrations is introduced. Damping is provided by incorporating VCDs in lieu of coupling beams in common structural configurations and therefore does not occupy any valuable architectural space, while mitigating building tenant vibration perception problems and reducing both the wind and earthquake responses of the structure. This paper provides an overview of this newly proposed system, its development, and its performance benefits as well as the overall seismic and wind design philosophy that it encompasses. Two tall building case studies incorporating VCDs are presented to demonstrate how the system results in more efficient designs. In the examples that are presented, the focus is on the wind and moderate earthquake responses that often govern the design of such tall slender structures while reference is made to other studies where the response of the system under severe seismic loading conditions is examined in more detail and where results from tests conducted on the viscoelastic material and the VCDs in full‐scale are presented. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

17.
The drift pushover analysis method for tall and regular buildings is extended in this paper to the third dimension. The focus of study is on the structures with important torsional response. For this purpose, 10, 15, 20 and 30-story steel moment frame buildings having unsymmetrical plans with 5–30% eccentricity ratios are studied. For evaluation of accuracy, nonlinear dynamic response of the buildings is determined under a consistent suit of earthquake ground motions. The maxima of the story drifts and shears and cumulative plastic hinge rotations of stories are calculated under the ground motions and their averages along with those of the modal pushover procedure are compared with the results of the presented method. The comparative analysis establishes the good accuracy of the three dimensional drift pushover method.  相似文献   

18.
对典型矩形高层建筑进行风洞试验,根据试验结果计算了各风向角下的等效静风荷载和风振响应,同时采用《建筑结构荷载规范》(GB50009-2012)计算方法对该建筑正交角度下的风荷载进行计算,结合风洞试验风荷载与规范计算结果,研究典型矩形高层建筑等效静风荷载和加速度响应分布规律。结果表明:结构基底风致响应最不利角度并非完全出现在正交角度,风洞试验楼层风荷载整体趋势与规范计算结果相同,数值上存在差异,宜以风洞试验结果为准,该结构的顶层加速度响应小于高规限值,舒适度满足要求。  相似文献   

19.
基于AR模型模拟超高层建筑的脉动风速时程   总被引:7,自引:0,他引:7  
风荷载是超高层建筑设计的主要荷载之一,而且通过风振时域分析可以更全面地了解超高层建筑风振响应特性,更直观地反映超高层建筑风致振动控制的有效性。因此,本文使用线性滤波法即白噪声滤波法(white noise filtration method,WNFM)中的自回归(auto-regressive,AR)模型模拟超高层建筑的风速时程。首先,考虑超高层建筑风速时程的时间和空间相关性,导出了四阶AR模型的参数表达式。接着,基于AR模型模拟了一幢高度为200 m超高层建筑的风速时程。最后,通过比较模拟风速功率谱、模拟自相关函数和互相关函数与目标风速功率谱、目标自相关函数和互相关函数的吻合程度,验证基于AR模型模拟超高层建筑风速时程的可行性。  相似文献   

20.
The Di Wang Tower located in Shenzhen has 79 storeys and is about 325 m high. Field measurements have been conducted to investigate the dynamic characteristics of the super‐tall building. In parallel with the field measurements, seven finite element models have been established to model the multi‐outrigger‐braced tall building and to analyse the effects of various arrangements of outrigger belts and vertical bracings on the dynamic characteristics and responses of the Di Wang Tower under the design wind load and earthquake action. The distributions of shear forces in vertical structural components along the building height are also presented and discussed. The results from detailed modelling of group shear walls with several types of finite elements are addressed and compared to investigate various modelling assumptions. Finally, the performance of the finite element models is evaluated by correlating the natural frequencies and mode shapes from the numerical analysis with the finite element models and the field measurements. The results generated from this study are expected to be of interest to professionals and researchers involved with the design of tall buildings. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号