关键词: 大型储罐, 抗震, 锚固系数, 设计准则

Abstract: Elephant foot buckling (axial compressive instability) of the lower part of tank wall, collision between floating roof and fixed roof, and overturning of storage tank as a whole are the common damage of large storage tank under earthquake load. For this reason, corresponding provisions were made in the U.S. and Chinese design codes for seismic design of large storage tanks. Combining with engineering cases, this paper focuses on comparing the differences between the anchorage coefficient, the maximum axial compressive stress of the bottom ring tank wall and the sloshing wave height in the seismic design calculation of the U.S. and Chinese design codes. The results show that for the calculation of anchorage coefficient, the domestic code took reference from the calculation formula of the American code, but didn’t take into account the impacts of the site category and the importance factor of the storage tank on the anchorage coefficient; for the calculation of axial compressive stress in the bottom ring wall, the domestic code expressions were similar to those in the American code in the case of anchorage or when the anchorage coefficient was not more than 0.785; the calculation results were mainly affected by the vertical seismic acceleration and coefficient of moment adjustment, while in other nonanchored cases, the difference between the two calculations was also affected by the different values of the buckling coefficient; for the calculation of sloshing wave height, the domestic code took the influence of tank shape into account, while the U.S. code took the influence of seismic use groups, the basic cycle of liquid storage sloshing, and the acceleration of the reaction spectrum into consideration.

Key words: large storage tank, anti-seismic, anchorage coefficient, design criteria