Numerical Studies On Elastic Stability And Dynamic Behavior Of Single-crossarm And Multi-crossarm Pre-stressed Stayed Column

As we know,steel structure building has some characteristics,such as light weight,high strength,convenient construction,good seismic performance and so on.Therefore it is widely used in in the construction,especially in industrial buildings.Some parts of bearing members in steel structure building is imposed prestressing force,which can effectively reduce the deformation,improve the structure performance,give full play to the strength of the material reserves.Pre-stressed stayed column,as a common kind of pre-stressed member in steel structure building,has beautiful shape and good mechanical performance,thus it is more and more applied in architectural design.Pre-stressed stayed column is a kind of modern pre-stressed steel structure,the tensioning prestressed steel cable provides lateral elastic constraints for the central steel column by the crossarm,which reduces the calculation length of a column,thus improves the buckling strength of the column.In this paper,on the basis of summarizing the predecessors' research works,the deep research on the pre-stressed stayed column is made.The main research content of this article includes:First,the destruction forms of the common column and the pre-stressed stayed column are introduced,including the whole instability and failure of the column,this paper sums up the theoretical basis and research conclusion of research object in this paper.Combined with the research object of this paper,element selection,boundary condition and prestress applying are expounded in finite element modeling process.This paper expounds the working principle and classification method of pre-stressed stayed column,and the analysis model is determined in this paper.The analysis of the elastic buckling load of the pre-stressed stayed column verify that prestressed cable system can improve stability bearing capacity and stiffness of core steel columns.On this basis,the influences of the prestress size,support conditions,the length and diameter of crossarm on stability bearing capacity of single-crossarm pre-stressed stayed column.Then the space single-crossarm pre-stressing stayed column is numerically simulated,and the simulated analysis results are compared with the theory of literature,the comparison results found the error between them is very small,which show that the theoretical analysis about space single-crossarm pre-stressed stayed column is correct in the literature.At the same time,the elastic buckling performance of multi-crossarm pre-stressed stayed column are numerically simulated in this paper,the elastic buckling load is larger than that ofthe single-crossarm pre-stressed stayed column.The reason is that the multi-crossarm pre-stressed system provides more lateral constraints to the center column,so as to improve its stability bearing capacity.In addition,the dynamic performance of the pre-stressed stayed column is also numerically simulated in this article,compared with the dynamic performance of the regular column,the pre-stressed crosss-arm system decrease the frequency of the pre-stressed stayed column and also has an impact on its modal shape.And then through the spectrum analysis,the maximum displacement and maximum stress of pre-stressed stayed column under the seismic action is smaller than that of common column,which show that pre-stressed stayed column has better seismic performance.