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低矮建筑屋面局部極值風壓特性的風洞試驗研究

發(fā)布時間:2018-04-22 09:07

  本文選題:低矮房屋 + 極值風壓; 參考:《湖南科技大學》2017年碩士論文


【摘要】:我國沿海地區(qū)分布著量大而廣的低矮建筑,每年受臺風影響造成巨大的損失。風災統(tǒng)計表明,低矮房屋的損毀主要表現(xiàn)為迎風屋面角部、邊緣和屋脊等易損部位先損毀并進而引發(fā)建筑的整體倒塌,而風壓極值往往是研究屋面局部風壓提高建筑抗風能力的關鍵。為此,本文采用風洞試驗方法,對雙坡低矮建筑屋面風壓概率分布特性、非高斯特性等極值特性以及極值估計方法展開研究,為我國低矮建筑抗風設計提供理論支撐。首先,本文采用縮尺比為1:20、體型比為1.5:1:1的風洞試驗剛性模型,以風向角、坡角和地貌為變量,針對雙坡低矮房屋表面風壓分布規(guī)律進行了分析,驗證了風洞試驗數(shù)據(jù)的準確性。探討了不同坡角、風向角及地貌下屋面風壓概率密度以及峰度與偏度分布特征并對概率密度分布進行了擬合分析。試驗結(jié)果表明,坡角的改變對屋面風壓高斯與非高斯區(qū)分布影響明顯,風向角與地貌的改變主要是對屋面來流分離區(qū)域偏度與峰度影響較大,但地貌的改變并未改變屋面偏度與峰度的變化規(guī)律。相比Gaussian分布與Gamma分布,GEV分布和Lognormal分布都能較好擬合不同工況下的屋面風壓概率密度分布。其次,基于風洞試驗數(shù)據(jù)對比分析了Quan法、Wang法和峰值因子法對屋面風壓極值的估計精度,同時探討坡角、風向角及地貌對幾種常用極值方法對應的風壓峰值因子取值的影響。試驗結(jié)果表明,Wang法較適用于低矮建筑屋面風壓極值估計。改進峰值因子法計算得到的峰值因子取值較為合理。最后,以風向角和屋面坡角為變量,探討了B類地貌下屋面局部分區(qū)陣風系數(shù)以及風壓極值的變化規(guī)律,同時與我國現(xiàn)行規(guī)范陣風系數(shù)取值進行了對比分析。結(jié)果表明,風向角對45°坡角低矮房屋迎風屋檐、屋脊、角部區(qū)域陣風系數(shù)影響較明顯。我國規(guī)范陣風系數(shù)和風壓極值的建議取值小于風洞試驗值,可能低估屋面局部設計風荷載,不利于結(jié)構(gòu)抗風。
[Abstract]:There are large and wide low buildings in coastal areas of China. Wind disaster statistics show that the damage of low-rise houses is mainly manifested in the corner of the upwind roof, the edge and the roof ridge and other vulnerable parts first damaged and then caused the overall collapse of the building. The extreme value of wind pressure is the key to study the local wind pressure of roof to improve building wind resistance. Therefore, in this paper, the wind tunnel test method is used to study the probability distribution characteristics of wind pressure, non- characteristics and extreme value estimation method of the roof of double-slope low-rise buildings, which provides theoretical support for the wind-resistant design of low-rise buildings in China. Firstly, a rigid wind tunnel test model with a scale ratio of 1: 20 and a figure ratio of 1.5: 1: 1 is adopted in this paper. The wind direction angle, slope angle and geomorphology are taken as variables, and the distribution of wind pressure on the surface of double-slope low-rise buildings is analyzed, and the accuracy of wind tunnel test data is verified. The probability density, kurtosis and skewness distribution of roof wind pressure under different slope angles, wind direction angles and geomorphology are discussed, and the distribution of probability density is analyzed by fitting. The results show that the change of slope angle has obvious influence on the distribution of roof wind pressure in Gao Si and non- area, and the change of wind direction angle and geomorphology mainly affects the deviation and kurtosis of roof flow separation area. But the change of geomorphology does not change the law of roof deviation and kurtosis. Compared with Gaussian distribution, Gamma distribution and Lognormal distribution, the probability density distribution of roof wind pressure under different working conditions can be fitted well. Secondly, based on the wind tunnel test data, the estimation accuracy of wind pressure extreme value of roof by Quan method and peak factor method is analyzed. At the same time, the influence of slope angle, wind direction angle and geomorphology on the value of wind pressure peak factor corresponding to several commonly used extreme value methods is discussed. The test results show that Wang's method is more suitable for estimating wind pressure extremum of low building roof. The value of peak factor calculated by improved peak factor method is reasonable. Finally, taking wind direction angle and roof slope angle as variables, the variation law of wind coefficient and wind pressure extreme value of local partitioning of roof under type B geomorphology are discussed, and the results are compared with the values of gusty wind coefficient in current codes of our country. The results show that the wind direction angle has an obvious effect on the gust coefficient in the eaves, ridges and corners of low buildings at 45 擄slope angle. The suggested values of gust coefficient and wind pressure extremum in the code of our country are smaller than those in wind tunnel test, which may underestimate the local design wind load of roof, which is unfavorable to the wind resistance of structures.
【學位授予單位】:湖南科技大學
【學位級別】:碩士
【學位授予年份】:2017
【分類號】:TU312.1

【參考文獻】

相關期刊論文 前10條

1 王旭;黃鵬;劉海明;余先鋒;;超強臺風作用下低矮建筑屋蓋風壓非高斯特性研究[J];建筑結(jié)構(gòu)學報;2016年10期

2 李波;田玉基;楊慶山;;非高斯風壓時程的矩模型變換與峰值因子計算公式[J];振動工程學報;2016年03期

3 莊翔;董欣;丁潔民;鄭毅敏;;矩形高層建筑表面風壓脈動的非高斯特性研究[J];建筑結(jié)構(gòu)學報;2016年S1期

4 李波;田玉基;楊慶山;范重;;平屋蓋圍護構(gòu)件設計風荷載研究[J];建筑結(jié)構(gòu)學報;2016年01期

5 李壽科;李壽英;陳政清;孫洪鑫;;圍護結(jié)構(gòu)非高斯風壓極值估計的改進Hermite峰值因子法[J];建筑結(jié)構(gòu)學報;2015年04期

6 田玉基;楊慶山;;非高斯風壓時程峰值因子的簡化計算式[J];建筑結(jié)構(gòu)學報;2015年03期

7 吳迪;武岳;孫瑛;;大跨度屋蓋結(jié)構(gòu)極值風壓概率分布特征研究[J];建筑結(jié)構(gòu)學報;2015年03期

8 潘小濤;黃銘楓;樓文娟;;復雜體型屋蓋表面風壓的高階統(tǒng)計量與非高斯峰值因子[J];工程力學;2014年10期

9 王相軍;戴益民;閆旭光;劉也;;低矮房屋表面平均風壓的數(shù)值模擬和實測及風洞試驗比較研究[J];建筑結(jié)構(gòu);2014年10期

10 黃鵬;蔡玢;全涌;顧明;;基于實測的低矮房屋屋面風壓極值計算方法[J];西南交通大學學報;2014年02期

相關會議論文 前1條

1 全涌;顧明;陳斌;;一種非高斯風壓系數(shù)極值計算方法[A];第十四屆全國結(jié)構(gòu)風工程學術會議論文集(下冊)[C];2009年

相關博士學位論文 前2條

1 胡尚瑜;臺風作用下低矮房屋風荷載現(xiàn)場實測和風洞試驗及理論分析研究[D];湖南大學;2012年

2 戴益民;低矮房屋風載特性的實測及風洞試驗研究[D];湖南大學;2010年

相關碩士學位論文 前2條

1 伍歡慶;風壓極值的閾值模型研究[D];湖南大學;2014年

2 陳龍;基于小容量樣本的屋蓋極值風荷載估計方法研究[D];哈爾濱工業(yè)大學;2013年



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