Analysis Of Seismic Response Of Spherical Tank Under Un-uniform Settlement Of Foundation

Compared with other pressure vessels,spherical tanks have many advantages,such as small floor area,high stress,high bearing capacity,easy installation and convenient transportation.Working in normal operation for a period of time in the spherical tank,often appear quality problems such as un-uniform settlement of foundation.Most of the spherical tank in this kind of problems,often accompanied by a pillar of the spherical tank tilt,will produce an additional stress in pillars.If the additional stress value is large,it may cause the pillar to exceed its maximum allowable stress,which may cause the instability of the spherical tank structure.Therefore,it is of great practical significance and engineering value to study the un-uniform settlement of spherical tanks.Based on the 1000m~3 spherical tank model,established the finite element model by using the SPH method and the equivalent mass method.The effect of coupling of liquid-structure on seismic response is discussed,the spherical tank model under un-uniform settlement of foundation is simulated and analyzed in the hydraulic test conditions and seismic conditions.The specific contents are as follows:Firstly,the Smoothed Particle Hydrodynamics Method(SPH)is introduced,and the basic principle of SPH method and the SPH method of Lagrange type Navier-Stokes equation are described.Secondly,the finite element model of experiments designed by Antoci is established by using the SPH method.The results of the numerical analysis and experimental comparison,proved the reliability and rationality of SPH method.Thirdly,the finite element model of spherical tank under the action of coupling of liquid-structure is established by using SPH method and the seismic response analysis is carried out by using the acceleration time history analysis method.The results show that the attenuation of the top displacement,the base shear force and the vertical force of the spherical tank under the action of coupling of liquid-structure are more rapid and the numerical results are much smaller than those of the additional mass method.It is proved that the coupling of liquid-structure has a significant effect on the seismic response of the spherical tank.Fourthly,considering the single pillar subsidence,the overall tilt in one direction,the middle sink and sink on both sides four settlement mode,the finite element model of1000m~3 spherical tank with liquid storage capacity of 89% is established,the stressdistribution of the column under the condition of water pressure test is analyzed.Fifthly,the coupling of liquid-structure finite element model of 400m~3,650m~3and1000m~3 spherical tanks was established by SPH method,and the influence of the volume of spherical tank under un-uniform settlement of foundation is analyzed.Sixthly,the finite element model of 1000m~3 spherical tank with liquid storage capacity of 89% is established by SPH method and equivalent mass method,the security analysis of a spherical tank column under four kinds of uneven foundation settlement is carried out,and the effects of different seismic waves on the uneven settlement of the spherical tank foundation are analyzed.