800m跨度柱面网壳室内外风场及风振响应特性研究

发布时间：2018-04-04 19:02

本文选题：800　切入点：m跨度柱面网壳　出处：《哈尔滨工业大学》2017年硕士论文

【摘要】：随着科技的发展,建造千米级“城市穹顶”成为了人们对未来建筑的设想。随着设想的提出,许多问题便成为了工程师们面临的挑战,如在大体量室内空间的风环境舒适性调控,穹顶外部的抗风问题等等。本文以800m跨度柱面网壳为例,对其室内外风场以及风振响应特性进行了研究分析,主要研究内容包括以下方面:1、800m跨度柱面网壳室内风环境研究基于CFD流体分析软件FLUENT,建立太阳照射和正常通风条件下室内风环境分析模型,探讨了自然通风口设置对室内风环境的影响。分析了自然通风不同进排风口大小、进排风口高差、排风口形式和不同密集程度建筑物群条件下通风效果的差异;研究了机械通风分层调控形式下不同气流组织形式和不同动力形式对室内风环境舒适度的影响。2、风压分布特性数值模拟和分析超大跨度建筑结构一般都具有质量轻、刚度小、自振频率低等特点,对风荷载十分敏感,其风压系数分布的研究对工程设计意义重大。规范对于相似外形的落地拱屋面的风荷载规定能否直接应用于800m跨度柱面网壳设计中,还不明确;因此,采用经过准确性验证的CFD数值模拟方法对不同形式的网壳进行风压系数分布的数值模拟,分析800m跨度柱面网壳的风荷载分布特性;将模拟结果和现行荷载规范对比,探讨规范条文的适用性,并且分析了风向角、矢跨比、尺寸效应和纵横比对风压系数分布的影响。结果表明,现行荷载规范条文无法直接应用于超大跨度柱面网壳的设计;矢跨比对风压系数的分布影响最大,纵横比的影响次之,矢跨比一定时,网壳结构风荷载尺度效应不明显。3、800m跨度柱面网壳风振响应特性分析基于MATLAB软件采用自回归方法对风速脉动进行数值模拟,根据模拟得到的脉动风速时程,建立800m跨度悬索支撑拱桁架结构有限元模型,进行了风振响应时程分析,研究了网壳的风振响应特性。分析得到800m跨度柱面网壳结构的风振系数,得到所有节点风振系数平均值为1.8;仅考虑平均风对结构的静力作用是不安全的,风速脉动引起结构的风振响应不可忽略。
[Abstract]:With the development of science and technology, the construction of kilometer-scale "urban dome" has become the vision of future architecture.With the development of the idea, many problems have become a challenge to engineers, such as the comfort control of wind environment in large indoor space, the wind resistance problem outside the dome and so on.Taking 800m span cylindrical reticulated shell as an example, the indoor and outdoor wind field and wind vibration response characteristics are studied and analyzed in this paper.The main research contents include the following aspects: 1: 1800m span cylindrical reticulated shell indoor wind environment research. Based on CFD fluid analysis software fluent, the indoor wind environment analysis model under solar irradiation and normal ventilation is established.The influence of natural vent setting on indoor wind environment is discussed.The difference of ventilation effect under the condition of natural ventilation with different size of inlet and outlet, the difference of inlet and outlet height, the form of outlet and the density of buildings were analyzed.In this paper, the effects of different airflow organization and different power forms on indoor wind environment comfort under the condition of mechanical ventilation stratification control are studied. Numerical simulation and analysis of wind pressure distribution characteristics are generally of light weight and low stiffness.Since the natural vibration frequency is low, it is sensitive to wind load, and the study of wind pressure coefficient distribution is of great significance to engineering design.It is not clear whether the specification of wind load of the similar shape of landing arch roof can be directly applied to the design of 800m span cylindrical latticed shell; therefore,The wind load distribution characteristics of 800m span cylindrical latticed shells are analyzed by numerical simulation of wind pressure coefficient distribution of different types of latticed shells by using CFD numerical simulation method, and the simulation results are compared with the current load codes.The applicability of the specification is discussed, and the effects of wind direction angle, rise-span ratio, dimension effect and aspect ratio on the distribution of wind pressure coefficient are analyzed.The results show that the current load code can not be directly applied to the design of super-span cylindrical latticed shells, the distribution of wind pressure coefficient is the most important, the aspect ratio is the second, and when the rise-span ratio is fixed, the distribution of wind pressure coefficient is the most important.Analysis of Wind Vibration response of Cylindrical latticed Shell with a Span of 3800m; numerical Simulation of Wind Velocity pulsation based on MATLAB Software, according to the time History of fluctuating Wind Velocity obtained by Simulation, the scale effect of Wind load on reticulated Shell structure is not obvious.The finite element model of 800m span suspension cable supported arch truss structure is established. The wind vibration response time history analysis is carried out and the wind vibration response characteristics of the latticed shell are studied.The wind vibration coefficient of 800 m span cylindrical latticed shell structure is obtained, and the average wind vibration coefficient of all nodes is 1.8. It is not safe to consider the static effect of average wind on the structure only, and the wind vibration response caused by wind speed pulsation can not be ignored.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU399;TU312.1

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