【摘要】 立式钢制圆柱形储罐向着大型化和浮放式发展,其动力特性参数,如结构的固有频率和固有振型,在地震工程中经常被使用,以15×104m3储罐为例,应用ADINA有限元程序,采用弹簧单元来模拟地基,考虑液固耦合效应对其进行了模态分析。结果表明:采用弹簧单元来模拟地基进行储罐的分析时,有限元与规范近似算法比较接近;15×104m3储罐液固耦合振动低频的振动形式比较丰富,以cosnθ、sinnθ型梁式振动为主,液体晃动低频的振动形式比较单一,即cosnθ、sinnθ型梁式振动;液固耦合振动频率对地基刚度最为敏感,储液高度与储罐高径比次之,受罐壁厚度的影响比较小;液体晃动频率对罐壁厚度和地基刚度不敏感,对储液高度与高径比则比较敏感。更多还原

【Abstract】 Large-scale unanchored vertical liquid storage tanks are being applied extensively,its dynamic parameters,such as the natural frequency and mode shape,are very often used in seismic engineering.The natural mode of 15×104m3 storage tank was analyzed by ADINA finite element technique using spring element to simulate foundation,and considering the liquid-structure interaction effect.The results show that: there is small difference between the finite element technique and the well-known code formula on mode analysis of tanks;the vibration forms of the low-frequency segment of 15×104m3 storage tank are various,among which cosnθ、sinnθ beam vibrations are the leading one,the vibration forms of the liquid are simple,namely cosnθ、sinnθ beam vibration;the frequencies of liquid-structure coupled vibration are sensitive to foundation stiffness,are followed by the liquid height and the ratio of tank height to radius,and are insensitive to the thickness of tank wall;sloshing frequencies of liquid are insensitive to foundation stiffness as well as the thickness of tank wall,and are sensitive to liquid height as well as the ratio of tank height to radius.更多还原