摘要
本文以一电厂脱硫烟囱为研究对象,建立了风致易损性模型。为了考虑风荷载的不确定性,运用谐波叠加法采用不同的风谱和风速来模拟结构所在地的风场。考虑材料参数的不确定性,得到不同的分析样本,并对样本逐一进行了非线性时程分析。以顶点位移作为损伤指标,通过线性回归分析在对数空间获得了风速与顶点位移之间的关系。接着继续考虑材料的不确定性,对结构进行静力弹塑性分析得到基底剪力-位移曲线,通过基底剪力-位移曲线获得不同极限状态的性能点,最后得到了不同风谱对应的风致易损性曲线。研究结果表明:不同风谱对烟囱性能的影响显著,其中Davenport谱的计算结果最为保守;在倒塌破坏时,其倒塌破坏风速很高,可以接近55 m/s。本文生成的易损性曲线,可进一步用于钢筋混凝土烟囱的风灾风险概率评估。
This paper develops a wind-induced susceptibility model for a power plant desulfurization chimney.In order to consider the uncertainty of wind loads,the harmonic superposition method is applied to simulate the wind field at the location of the structure using different wind spectra and wind speeds.Different analysis samples were obtained to take the uncertainty of material parameters into account,and a nonlinear time-course analysis was carried out for each sample.The relationship between wind speed and vertex displacement was obtained by linear regression analysis in logarithmic space using vertex displacement as the damage indicator.Then the material uncertainty was continued to be considered,and the base shear-displacement curves were obtained by static elastoplastic analysis of the structure.The performance points of different limit states were obtained through the base shear-displacement curves,and finally,the wind-induced susceptibility curves corresponding to different wind spectra were obtained.The results show that the different wind spectra have significant effects on the performance of the chimney,among which the Davenport spectrum has the most conservative calculation results;its collapse damage wind speed is high at collapse damage,which can be close to 55 m/s.The susceptibility curves generated in this paper can be further used for the wind risk probability assessment of chimneys with reinforced concrete.
作者
蒋新华
范存新
JIANG Xin-hua;FAN Cun-xin(School of Civil Engineering,Suzhou University of Science and Technology,Suzhou 215011)
出处
《广州建筑》
2022年第3期8-15,共8页
GUANGZHOU ARCHITECTURE
关键词
风致易损性
脉动风
非线性时程分析
回归分析
对数正态分布
wind-induced vulnerability
pulsating wind
nonlinear time history analysis
regression analysis
lognormal distribution
