台风作用下超高层建筑气动阻尼原型实测研究

The main aims of this project are to study the aerodynamic damping characteristics and basic mechanism on super-tall buildings under typhoon by field research, field measurements and theory analysis. Base on the measurements investigation, this project plans to establish several field measurement bases which can satisfy the field measurements of wind-induced response on several typical super-tall buildings in typhoon-prone regions in coastal city. The field measurement data base will be established through a large amount of field measurements. And according to ITD theory combining RDT and ERA theory , the structural modal parameter and the all wind direction varying characteristics of aerodynamic damping on several typical super-tall buildings will be obtained during the passage of typhoon. Furthermore, the contrastive analysis of field measurements results with the existing wind tunnel research results in the world will be carried on, and to deepen the understanding of wind-induced response characteristics on super-tall building in coastal city during the passage of typhoon. Generally, based on the summarized parameters of wind resistance design, the research results in this project is very useful and be of great significance to improve the anti-typhoon ability of super-tall buildings, to accumulate data for the modify of codes, and to solve some fundamental issues of the aerodynamic damping in super-tall building research region.

本项目采用实地调研、现场实测和理论分析方法，研究台风作用下沿海城市超高层建筑的气动阻尼变化的规律特性和基本机理。拟在沿海台风多发区域实地调研基础上，选择多幢典型体型超高层建筑为试验对象并在其上构建风场及结构风致响应实测系统，在台风期开展大量的原型实测，建立实测数据库。运用随机减量技术、易卜拉欣时域法、特征系统实现算法等理论，分析获取在台风作用下典型体型超高层建筑的相关结构模态参数及全风向气动阻尼变化规律，特别是全风向下气动阻尼与风速风场、建筑型态、结构模态参数之间的关系规律，并寻求与风洞实验的理论结果进行对比研究，以期解决超高层建筑气动阻尼研究的一二个基础性问题。本项目关于台风作用下沿海城市超高层建筑的气动阻尼变化特性的深化认识，对提高抗风设计能力、防灾减灾具有重要的社会意义和应用价值。

本项目采用实地调研、原型实测、风洞试验和理论分析等研究方法，对具代表性的沿海特定地貌环境下风场变化机理以及台风下沿海城市超高层建筑顶部风场及其结构风致响应规律进行了系统深入地分析研究。首先在沿海地区典型地貌下，运用指数律、对数律和D-H模型等理论方法探索常态风、季风、灾害风下的风廓线性质特点，而且使用F-检验方法探究其相关性，还进一步深入研究了基于台风登陆前后不同时期实测数据的风剖面、边界层高度、竖向平均风速等的演变特征。其次在台风多发区域实地调研基础上，选择典型体型超高层建筑为试验对象并在其上构建风场及结构风致响应实测系统，建立了超高层建筑抗风实测基地，建立实测数据库。通过现场实测获得了建筑结构顶部平均风速风向、湍流强度、阵风因子、峰值因子、湍流积分尺度、脉动风速谱以及湍流相关性等风场特性；获得了环境激励、台风影响等多种方式下超高层建筑的前五阶模态的性状，并分析探索了该建筑结构气动阻尼比的影响因素，尤其与折减风速的关系规律；同时研究了超高层建筑围护结构风压在不同风向角下的脉动特性，以及与风洞实验结果比较的基本一致性。本项目关于台风作用下沿海城市风场性质的研究及超高层建筑的气动阻尼变化特性的深刻认识，对于人类社会防灾减灾具有重要的应用价值。