基于弹性基础的大型石油储罐结构优化分析

The Optimization of Large Oil Storage Tank on Flexible Foundation

国内已先后兴建了一批容积为10万立方米大型石油储罐,但实测结果和理论分析均表明,无论是按日本工业标准JISB8501设计的,还是按美国API650标准设计的,现有油罐罐壁受力情况并非处于理想状态。本文采用基于弹性基础的外壁面环向应力理论计算式,对大型油罐的罐壁结构进行了优化分析,结果表明只要适当增大下面第1层壁板的宽度,或尽量减小下面第1层与第2层壁板的厚度差δΔ,就可以降低罐壁最大应力峰值,改善应力分布状况,同时还能降低制造与安装成本。

With the development of the China, there are many large oil storage tanks established these years. The proper stress is the necessary condition to insure the safety of the tank. Authors have measured three large oil storage tanks and got first-hand data of the shell wall's stresses. Comparison between the theoretical stress and measured values of 10×104m3 oil storage tanks shows that the stress distribution of the first and second shell wall, especially at the first girth joint of two shells is not optimum. Based on JIS B 8501 or API650, the design methods of the oil storage tanks are not the best. The optimization for a mechanic model of a 10×104m3 oil storage tank considering the flexible foundation is proposed in this paper. The result shows that the maximum stress can be reduced through increasing the width of the first shell wall or reducing the difference of the first and the second shell wall thickness(δΔ). The stress distribution of the walls will be better than the traditional structure. At the same time, the requirement for the first girth joint is fell, so the fabrication and installation cost of the tank could be reduced.