Study On Eccentric Compression Performance Of T-shaped Composite Column Of Modular Wall Light Steel Concrete Frame Structure

In recent years,due to the advantages of convenient assembly,low cost and low environmental pollution,prefabricated buildings in China have shown a trend of continuous growth.However,the use of traditional reinforced concrete composite columns in prefabricated buildings is bound to cause waste of indoor space and affect the appearance and function of buildings.Therefore,this thesis proposes a new type of T-shaped light steel composite column that can be integrated into an assembled frame structure by combining I-shaped steel beams,that is,single-limb cold-formed thinwalled steel is assembled by self-tapping screws to form a T-shaped light steel skeleton,and then concrete is poured to form a T-shaped light steel composite column.This structure has good overall stability and high bearing capacity;at the same time,the structure also has the advantages of light weight,material saving and material saving.In order to evaluate the mechanical properties of the composite column,according to the characteristics of practical application,the composite column is subjected to twoway bias test,finite element analysis and theoretical research.The specific research process of T-type light steel composite column is as follows :(1)The static loading test of T-shaped light steel concrete composite column specimens was carried out by changing the parameters such as steel thickness,eccentricity and eccentricity angle.The ultimate bearing capacity and deformation characteristics of T-shaped light steel concrete composite columns under bidirectional eccentric load were studied.Through the analysis of the test results,the failure mode,stress distribution and deformation law of the composite column structure are revealed.(2)In order to verify and optimize the design method of T-shaped light steel concrete composite columns,a nonlinear finite element model was established by ABAQUS finite element analysis software,and the model was parameterized and material properties were defined according to the material test data.The finite element simulation results are compared with the experimental results,and the rationality and accuracy of the finite element model are evaluated.(3)On the basis of ensuring that the finite element analysis results are consistent with the experimental results,this thesis further analyzes the parameter expansion of the full-scale structural model,and discusses the influence degree and trend of different eccentricity distance,steel thickness,slenderness ratio and eccentricity angle on the ultimate bearing capacity and deformation capacity of T-shaped light steel concrete composite columns.(4)Firstly,the principle and application scope of the calculation method of axial compression bearing capacity and biaxial eccentric compression bearing capacity of composite special-shaped columns in the current code JGJ 138-2016,European code Eurocode 4 and North American code ANSI / AISC 360-10 are introduced.Secondly,according to the results of each parameter model calculated by ABAQUS finite element software,the ultimate bearing capacity of T-shaped light steel concrete composite columns is analyzed,and the formulas of axial compression bearing capacity,flexural bearing capacity and bidirectional eccentric compression bearing capacity of T-shaped light steel concrete composite columns are derived.