钢结构电视塔风荷载动力研究

发布时间：2018-06-25 08:44

本文选题：钢结构电视塔 + 拟静力风荷载　；参考：《郑州大学》2013年硕士论文

【摘要】：电视塔是一种典型的高耸结构,而钢结构以其自身的特点往往作为电视塔结构的首选方案。随着社会的发展,电视塔由原来只能发射讯号的单功能电视信号发射向通讯、展览、旅游、广告等文化活动和商业活动的大型综合电视塔发展。电视塔往往是一个城市的标志性建筑。电视塔结构属高柔结构,作用在其上的荷载以风荷载为主要的控制荷载。由于电视塔的多功能要求,对于电视塔结构的抗风要求越来越高。但钢结构电视塔对风荷载更为敏感,电视塔在风荷载作用下损坏的例子是屡见不鲜。所以对于钢结构电视塔的设计,风荷载的动力效应计算显得尤为重要。本文首先本文介绍了脉动风荷载的模拟方法及实现过程,利用线性滤波法(AR法)模拟风速时程,编写了脉动风模拟程序。编制出的风荷载时程曲线程序适合于一般高耸结构脉动风荷载的模拟。本文通过对既有的某不上人电视塔(模型一)和上人电视塔的(模型二)风荷载拟静力分析,按照高耸规范对钢结构电视塔进行了0。和45。两个风向角作用下的风荷载响应分析,得到电视塔在风荷载作用下受45。风向控制的结论。本文对比了两个不同天线刚度的电视塔风荷载拟静力分析与动力时程分析,分析得到带天线的电视塔按规范只考虑第一振型的影响来计算风荷载会产生较大的误差。同时对两个电视塔在有天线和无天线两种情况下的进行了模态分析,观察两个电视塔在两种情况下的振型情况,发现带有天线的电视塔的高振型影响不可忽略,当天线去掉时,高振型影响较小,天线对电视塔结构的自振频率影响较为显著。本文最后通过改变模型一的三维有限元模型中的天线刚度,进行电视塔风荷载拟静力分析结果与动力时程分析结果的吻合程度的研究。研究表明,对于中小型电视塔,天线高度为20米左右,当天线顶端与塔身顶点在天线顶点处施加一个单位力产生的位移比小于5倍时,电视塔整体结构的风荷载可按规范仅考虑第一振型的影响来计算；若该位移比大于5倍,则电视塔整体结构风荷载按时程分析方法进行风荷载计算或将规范中的风荷载适当乘以一个放大系数。
[Abstract]:TV Tower is a typical high rise structure, and the steel structure is often the first choice of TV tower structure because of its own characteristics. With the development of the society, the TV Tower is developed from the original single function television signal transmitting signal to communication, exhibition, tourism, advertising and other cultural activities and commercial activities. The tower is often a landmark in a city.
The structure of TV Tower is a kind of high flexible structure, the load acting on it is mainly controlled by wind load. Because of the multi-function requirement of the TV Tower, the demand for wind resistance of the TV tower structure is getting higher and higher. But the steel structure TV Tower is more sensitive to the wind load, and the example of the damage of the TV Tower under the wind load is common. The design of structure TV Tower is particularly important for calculating the dynamic effect of wind load.
This paper first introduces the simulation method and the realization process of the fluctuating wind load. Using the linear filtering method (AR method) to simulate the wind speed time history, the simulation program of pulsating wind is written. The program of the wind load time history curve is suitable for the simulation of the fluctuating wind load of the general high rise structure.
In this paper, through the static analysis of the wind load of the existing TV Tower (model one) and the upper human TV Tower (model two), the wind load response of the steel structure TV Tower under the action of 0. and 45. two wind angles is analyzed according to the high rise standard, and the conclusion of the control of the 45. wind direction under the wind load is obtained.
In this paper, the quasi static analysis and dynamic time history analysis of the wind load of two TV towers with different antenna stiffness are compared. It is analyzed that the TV Tower with the antenna can only calculate the wind load according to the influence of the first mode of vibration. At the same time, the modal analysis of the two TV towers in two cases with antenna and no antenna is carried out. The vibration mode of two TV towers in two cases is observed. It is found that the high vibration mode of the TV Tower with antenna can not be ignored. When the antenna is removed, the influence of the high vibration mode is smaller. The antenna has a more significant influence on the frequency of the structure of the TV tower.
At the end of this paper, by changing the antenna stiffness in the three-dimensional finite element model of the model one, the agreement between the static analysis results of the wind load of the TV Tower and the result of the dynamic time history analysis is studied. The study shows that the height of the antenna is about 20 meters for the medium and small TV Tower, and when the top of the antenna is applied to the vertex of the antenna at the vertex of the antenna, the antenna is applied to the vertex of the antenna. When the displacement ratio of unit force is less than 5 times, the wind load of the overall structure of the TV tower can be calculated according to the effect of the first vibration mode only. If the displacement ratio is more than 5 times, the wind load of the whole structure of the TV Tower is calculated by the wind load or the wind load in the norm is multiplied by a magnification factor properly.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU391;TU312.1

【参考文献】