Study On The Bearing Capacity Of Short Columns With Round Stainless Steel Tube Under Axial And Eccentric Pressure

In recent years,the development of the construction industry began to gradually transform to green buildings and prefabricated buildings,and the construction industry began to use more steel structures and composite structures.However,the corrosion resistance and high maintenance cost restrict the large-scale application of steel columns and composite columns in traditional buildings.In order to solve this problem without significantly increasing the cost,researchers thought of using stainless steel pipe instead of traditional steel pipe.Stainless steel tube concrete structure has good mechanical properties of ordinary concrete-filled steel tube and superior corrosion resistance and durability of stainless steel.It has beautiful appearance,long service life,good ductility,seismic performance and fire resistance.It is very suitable for long-span structure or high-rise buildings,At the same time,it has a wide application prospect in the marine environment and other application scenarios with high requirements for durability and corrosion resistance.In this paper,the experimental study and numerical simulation analysis on the axial and eccentric compression performance of circular stainless steel tube concrete short columns are carried out:(1)The experimental study on 8 specimens of concrete-filled circular stainless steel tubular stub columns(including 2 eccentric compression specimens and 6 axial compression specimens)has been completed.The specific parameters of the specimens are shown in Table2.3.The main parameters are length diameter ratio(axial pressure)and eccentricity(bias).During the test,the strain of stainless steel tube and the development process of the overall deformation of the component are monitored at the key points,and the failure mode and stress mechanism of the component are analyzed.The test results show that the circular stainless steel tube concrete short column has high bearing capacity and good ductility,and the stainless steel tube can still play an effective role in restraining the concrete after the peak load.Compared with axial compression members,the bending moment of eccentric compression members significantly reduces the bearing capacity of members.The effects of different parameters on load axial displacement curve and bearing capacity were investigated by experiments.Finally,the current "Fujian engineering construction standard DBJ / T 13-51-2010" and other specifications and literature methods are used to calculate and compare the axial and eccentric ultimate bearing capacity of the collected specimens,so as to explore the applicability of the existing concrete filled steel tube codes for the calculation of the bearing capacity of stainless steel tube concrete members.(2)In the aspect of numerical simulation,this paper establishes the numerical simulation model of circular stainless steel tube concrete short column through ABAQUS,and on the basis of verifying the accuracy of the finite element model,analyzes the parameters and stress nephogram of the influence factors such as length diameter ratio,eccentricity and core concrete strength,In order to provide technical reference for more reasonable design of stainless steel tube concrete structure and engineering practice,and also provide basic data for the formulation of relevant design specifications.