15×10~4m~3超大型油罐应力测试与数值模拟分析

兰州原油末站大型油罐群,是我国首次在饱和黄土地基修建的大型储油设施。依托其中一座15×104 m3超大型非锚固油罐,开展了现场充水测试罐壁静态应力的试验研究。通过粘贴在油罐罐壁的应变计,测试充水过程中罐壁应力的变化规律,并采用有限元对15×104 m3超大型油罐进行应力分析。测试结果表明:罐壁的环向应力随充水水位的增加基本呈线性关系。数值模拟计算表明,罐壁环向应力最大值发生在第二圈罐壁和第三圈罐壁相连接的位置。由于罐壁上部设置了抗风圈和加强圈,有效地控制了罐壁的径向位移,使罐壁环向应力和竖向轴向应力在加强圈和抗风圈附近发生波动。将有限元数值模拟计算的罐壁环向应力分布情况与实测应力进行比较,两者总体吻合较好。上述研究结果可为超大型储罐在黄土地基的设计和建造提供技术依据和设计参数验证。

Stress Measurement and Numerical Simulation of 15 × 104 m3 Extra-Large Oil Tank

Large oil storage tank group of Lanzhou crude oil terminal station is the first large oil storage facilities built on saturated loess ground in China. An extra-huge (15×10⁴ m³ in volume) and unanchored oil storage tank was selected from the tank group to carry out spot water filling experimental study of tank wall static stress measurement. Through strain gauges pasted on the oil tank wall, tank wall stress variation in water filling process was measured, and the results were analyzed by finite element method. Measurement results show that tank wall circumferential stress presents basically a linear relationship with water level increase in water filling process. Numerical simulation results show that the maximum value of tank wall circumferential stress occurs at the position connecting the second lap and the third lap of tank wall. Due to wind ring and stiffening ring set at the upper part of oil tank wall, which effectively control tank wall radial displacement, so the circumferential stress and vertical axis stress fluctuate near the wind ring and stiffening ring. Comparing calculated tank wall circumferential stress distribution from finite element numerical simulation with that from spot measurement result, it can find out that both are in an overall good agreement. Above results provide a technical basis and design parameters validation for design and construction of extra-large oil tank constructed on the saturated loess stratum.