大型立式浮顶储罐基础隔震数值研究

Numerical research on large base isolation vertical storage tanks with floating roof

强震作用下,立式浮顶储罐破坏严重。为了降低浮顶储罐的地震响应,选取15×104m3大型立式浮顶储罐,引入基础隔震措施,并考虑浮顶的影响,应用势流体理论,采用ADINA建立有限元模型。研究在不同隔震层阻尼比、不同隔震周期、不同烈度及不同场地条件影响下,基础隔震浮顶储罐的地震响应并进行对比分析。结果表明:当隔震层阻尼比为0.2～0.3时减震效果较好,阻尼比存在合理优化区间;随着隔震周期、地震烈度的增加,基础隔震浮顶储罐的减震率增加;基础隔震浮顶储罐的减震效应受场地条件影响较大;基础隔震措施不能有效控制浮顶储罐的晃动波高。浮顶储罐隔震设计时需要综合考虑多种因素,选取最佳隔震设计参数。

The vertical storage tanks with floating roof are usually badly damaged in the strong earthquake. In order to reduce seismic response of vertical storage tanks, selecting 15 × 10^4m^3 storage tank, the base isolation system was introduced and allowing for the impact of floating roof. Based on potential fluid theory, the finite element mod- els were established by using ADINA. The seismic response of base isolation vertical storage tank with different fac- tors such as isolation layer damping ratio, isolation periods, different site conditions and seismic intensity were cal- culated and comparativey analyzed. The results indicate that when isolation layer damping ratio close to 0.2 ~ 0.3 the effect of seismic isolation is best and there is a reasonable range of damping ratio optimization. The vibration re- duction rate of base isolation vertical storage tanks with floating roof increases with the increase of isolation period and seismic intensity. Site conditions have a big influence on the vibration neduetion effect of base isolation vertical storage tanks with floating roof. Isolation measures can not effectively control the sloshing wave height. Isolation earthquake design of storage tanks with floating roof must consider a variety of factors and select the best isolation design parameters.