Comparison Of Different Analytical Approaches On Frame-core Tube Structure Of High-rise Building

This paper made a comparative study on different analytical approaches on frame-core tube structure of high-rise building subjected to lateral load considering shear lag.As a solution method to analysis the outer frame,equivalent continuum method is accurate because of considering the shear lag influence.This paper base on the equivalent continuum theory of High-rise Building,transformed the outer frame of frame-core.Then using force method and differential equation method to analysis.Last but not least,this paper put forward a simply modeling method on the software of ANSYS,then this result are compared with the original model.The major work performed is detailed as follows.(1)First,base on equivalent continuum theory of High-rise Building binding,transforming the outer frame of frame-core tube structure into equivalent orthotropic plate,list the formulations of column and girder internal force and the deflection displacement of the outer frame independent bearing three usual types of lateral load considering shear lag.Then depending on the formulations of the outer frame,the formulations of column and girder internal force and the deflection displacement of frame-core tube structure considering shear lag were list out by using force method and differential equation method.(2)The formulations in above paragraph were be used with a engineering example of frame-core tube structure.Making a comparative analysis of three different hand-calculation methods of frame force and lateral displacements: equivalent continuum method result of the outer frame,equivalent continuum force method of frame-core tube structure and equivalent continuum differential equation method of frame-core tube structure.And then using the finite element software ANSYS to make a model of the frame-core tube structure,in this model the beam element is used to simulate column and girder,the shell element is used to simulate shear walls.This paper made a comparative analysis between finite element results and hand-calculation methods’ results.The author found that the finite element results are similar to the hand-calculation methods’ results,which proof that the equivalent continuum method can approximate calculation the shear lag effect of frame-core tube structure.(3)The author put forward a simply modeling method of frame-core tube structure depend on equivalent continuum,which transforming the outer frame of frame-core tube structure into equivalent orthotropic plate in the modeling process.When the high building structure changed,the designers could change the plate thickness and material parameters on its implementation.At last,the author made a comparative analysis between the simply modeling and the whole model on its static and dynamic characteristics to prove the feasibility of simply modeling method.After the comparative study,the author draw the conclusions that the hand-calculation methods depends on equivalent continuum can simulate the stress characteristics of frame-core tube structure but has low practicability.In the preliminary design,the designer could used the simply modeling method to create the finite element model of building,which can estimate the stress characteristics of frame-core tube structure.In the final phase,when the designer create the whole structure model,the simply modeling result can provide a manual checking of the computer analysis results.