LNG储罐多点整体提升过程的力学性能研究

Research on Mechanical Properties of Multi-point Integral Lifting Process of LNG Storage Tank

某LNG储罐采用计算机多点控制的倒装法液压提升技术来进行施工。提升过程中由于储罐的跨度大、罐壁薄、质量重,其在提升过程中易发生罐壁变形甚至失稳破坏等问题,故需要对其提升过程进行力学模拟。采用ABAQUS建立罐体有限元模型,对其在施工状态下由于提升误差引起不同步提升进行模拟,发现有12.9%的概率出现提升点应力集中,导致结构局部屈曲。为此建立胀圈法提升改进模型,对比发现,结构最大应力减小至135 MPa,满足结构稳定的要求。

The inversion hydraulic lifting technique of computer multi-point control was used for the construction of a LNG storage tank.During the lifting process,due to the long span,thin wall and heavy mass of the tank,the tank wall was prone to deformation and even instability damage during the lifting process,so it was necessary to conduct mechanical simulation of the lifting process.ABAQUS was used to establish the finite element model of the tank body and simulate the asynchronous lifting caused by the lifting error under the construction state,it was found that there was a 12.9%probability of occurrence of stress concentration,which would result in local buckling of the structure.The improved model based on expanding circle method was established and compared with the asynchronous lifting results,the results showed that the maximum stress of the structure should be reduced to 135 MPa,so as to meet the requirements of structural stability.