风载荷作用下立式低温储罐动力可靠性分析  

Dynamic reliability analysis of vertical cryogenic tank under wind load

作　　者：刘明[1] 郑亚明 多依丽[1] 赵超 LIU Ming;ZHENG Yaming;DUO Yili;ZHAO Chao(School of Environment and Safety Engineering,Liaoning Shihua University,Fushun Liaoning 113001,China)

机构地区：[1]辽宁石油化工大学环境与安全工程学院,辽宁抚顺113001

出　　处：《中国安全科学学报》2020年第1期48-52,共5页China Safety Science Journal

基　　金：“十三五”国家重点研发计划项目(2018YFC0808500)。

摘　　要：针对随机风载荷作用下储罐结构动力可靠性问题,以300 m^3的中小型立式低温储罐为研究对象,利用自回归(AR)模型进行数值模拟,得到风载荷的脉动风速时程与脉动功率谱密度函数;采用ANSYS程序建立储罐三维有限元模型,并对储罐进行动力学分析,计算出储罐结构的随机响应值,进而得到随机风载荷作用下储罐结构动力可靠性所需全部数字特征;利用首次超越机制计算得到储罐的动力可靠度。结果表明:在50年一遇高度为10 m处最大风速26. 8 m/s的情况下,振动频率为0. 83 Hz时,结构位移、速度响应幅值比较大,储罐对低频振动比较敏感;随着使用年限的增加,储罐结构动力可靠度呈现出负指数形式下降趋势,当储罐达到设计使用年限25年时,可靠度降为71. 46%。In order to study dynamic reliability of storage tank structure under random wind load,with a 300 m^3 small and medium-sized vertical cryogenic tank as research object,pulsating wind speed time series and pulsating power spectral density function of wind load were numerically simulated by using AR model.Then,a three-dimensional finite element model of storage tank was established by ANSYS,and dynamic analysis of the tank was carried out to calculate random response value of storage tank structure before all digital features required for its dynamic reliability under random wind load were obtained. Finally,dynamic reliability was calculated by using first transcendence mechanism. The results show that under the condition of maximum wind speed of 26. 8 m/s 10 m high in 50 years,structure displacement and velocity response amplitude are relatively large and storage tank is comparatively sensitive to low frequency vibration when vibration frequency is 0. 83 Hz. With the increase of service life,dynamic reliability of storage tank structure presents a negative exponential decline trend,which will drop to 71. 46% when designed service life of storage tank reaches 25 years.

关 键 词：立式低温储罐 风载荷 自回归(AR)模型 首次超越机制 动力可靠性 

分 类 号：X944.4[环境科学与工程—安全科学]