中美大型储罐设计标准抗震计算对比

Comparison between Chinese and American design standards of anti-seismic calculation for large-scale storage tank

基于石油储罐设计日益大型化和浮放式的现状,对比分析了现行中美大型储罐设计标准GB50341-2003和API650-2012关于抗震计算的相关规定,总结了其在抗震设防基准、设计准则、数学模型及其参数和计算方法等方面的差异。依据两国标准规定的方法,对某项目5000m3内浮顶罐的抗震计算不同,尤其是罐壁临界许用应力,两标准的计算结果相差近3倍,是所有计算结果中差别最大的参数,也是两者设防目标不同在数值上的表现。GB50341-2003规定储罐上部自由空间即为晃动波高,而API650-2012规定储罐上部自由空间的确定需要充分考虑储罐地震用途组别等因素,更有针对性地定义了储罐上部自由空间与晃动波高的关系。(表3,参8)

Based on the status quo of increasingly upsizing and free standing oil tank, contrastive analysis is conducted for relevant regulations of Chinese and American design standards （GB 50341 --2003 and API 650-2012） for large-scale storage tank on the seismic calculation to summarize the differences in the seismic fortification basis, design criteria, mathematical model as well as its parameters and calculation methods. The methods specified in Chinese and American standards produce different seismic calculations for the 5 000 m3 covered floating roof tank in the project. Especially with respect to the critical allowable stress of the tank wall, the difference in calculation results of both standards can be nearly 3 times as large. It is the parameter with the biggest difference of calculation results but also the numerical reflection of different fortification objectives in both standards. GB 50341--2003 specifies the top free space of the storage tank as the sloshing wave height, while API 650-2012 specifies that the top free space of the storage tank shall be determined in full consideration of tank seismic purpose, group and other factors to more accurately define the relationship between the top free space and sloshing wave height of storage tank. （3 Tables, 8 References）