| The prestressed concrete shallow silos have been widely used for its good integrity, easy construction, lower cost, etc. But its complicated stress characteristics, especially the large-diameter shell structure are often the main reasons leading to structural damage. Research has found that the earthquake is the main factor in leading the damage of silo structure, thus it is important to evaluate the seismic and calculate the earthquake action.This paper reviewes the silo's development history in China and summarized recent study of silos seismic design at home and abroad, then it introduces the current theoretical analysis method of the silo seismic design. Following work have been done on these bases:Fristly by analysing the static and dynamic characteristics of the large-diameter concrete shallow silo by FEM analysis software (ANSYS), the paper discussed the deformation, stress characteristics and the seismic behavior of the whole structure, thus provide a reference for this kind of structure design according to practical work.Secondly according to the Principle of Equivalent of the Quality and Stiffness, the author simplified the original structure, derived calculation formula of the simplified model, built the one-dimensional simplified model and realized the transformation of three dimension structure to one dmension structure.Thirdly comparing with the seismic action and the dynamic characteristics of the original structure,the natural vibration frequency, period,or the response spectrum analysis and time history analysis under the seismic action all have mathced perfactly with the the shear force, displacement,calculated with the original data structure,verify the rationality of this simplified equivalent model.Fourthly applying hybrid programming ideas, this paper set up ANSYS and MATLAB data interface between the two kinds of software and realized the integrigation of model simplification and seismic operations analysis process. Such methods are simple and practical, it can improve the efficiency and accuracy of seismic calculations which can meet the engineering needs thus it is of high value of tapplication and promotion.Fifthly through a 12-storey frame shear wall numerical example,this paper further verifies the rationality and applicability of the simplified model.The resultes of comparation of operations process showed that the simplified calculation method proposed by this paper enjoyes a wide applicability and can be applied to the general structure. Example shows that this simplified analysis method used in seismic design of structures can be optimized to improve its security and economy,to provides practical and economic reference for seismic design. |
