软土地基大型油罐沉降数值分析

Numerical Analysis on Settlement of Large-scale Oil Tank on Soft Foundation

文章以广西石化1 000万t/a炼油项目为背景,建立软土地基大型油罐沿环墙圆周方向展开的二维有限元模型。基于该模型计算出环墙最大和最小沉降点,沿通过最大或最小沉降点的环墙径向建立了相应的二维轴对称模型,并进行模拟计算,分析了这两个关键点所在的油罐底板沉降特征。基于油罐最大沉降点沉降值,反演出合适的均布荷载,并在该荷载下对整个环墙沉降进行模拟计算,并与环墙实际监测结果进行了对比。模拟结果表明:二维有限元模拟方法适用于软土地基油罐沉降分析;素填土是油罐沉降控制的关键,对素填土进行加固处理可实现对油罐沉降控制;油罐沉降是一个长期的过程,需加强后期监测与控制。所得结论可为类似工程设计提供参考。

Based on the Guangxi Petrochemical 1 Mt/a Refinery Project,2D FEM numerical analysis model of large-scale oil tank on soft foundation was built along ring-wall circumferential direction. With that 2D model,the maximum and minimum settlement points were determined. 2D radial axisymmetric models with the maximum and minimum settlement points were respectively built and simulation calculations were carried out. Settlement characteristics of the tank bottom plate,where those two key settlement points located,were analyzed. Based on the settlement value of the maximum point,suitable uniformly distributed load was got by inversed calculation. Under that load,the whole ring-wall settlement was simulated. Besides, the simulation and monitoring results of the ring-wall were compared. Some conclusions were drawn,such as 2D FEM numerical method was feasible for large oil tank settlement analysis in soft foundation;plain fill was the key to control oil tank settlement,and it needed to be reinforced in order to control tank settlement. The settlement of oil tank is a long term course,long-term monitoring and control should be taken in the future. The results are useful for similar projects.