Study On Overall Stability Of High-Strength Hot-Rolled Circular Steel Tubes Under Combined Compressive Axial Load And Bending

Although China's "Standard for design of steel structures" GB50017-2017 supplemented the relevant design requirements for Q460 steel and components,the research on the overall stability of high-strength hot-rolled circular steel tubes under combined compressive axial load and bending has not been systematically studied yet,and lacks sufficient test data support.Therefore,in this paper,combined with experimental research and numerical simulation methods,in-depth study of the overall stability of Q460 hot-rolled circular steel tubes under combined compressive axial load and bending and put forward reasonable design suggestions.The main work of this article is as follows:(1)Complete the eccentric compression performance test of 5 full-scale models of Q460 hot-rolled circular steel tube members,obtain the deformation development,instability failure mode and overall stability ultimate bearing capacity of the members under combined compressive axial load and bending,and compared the test results with the relevant provisions of multi-country design codes.(2)ABAQUS was used to establish a reliable finite element model considering initial defects,and the test results of each specimen were simulated;further large-scale parameter analysis was carried out on the Q460 hot-rolled circular steel tubes under combined compressive axial load and bending to investigate the slenderness ratio,eccentricity and The influence of the diameter-thickness ratio parameter on its overall stability performance.The results show that the overall stable bearing capacity of highstrength hot-rolled seamless circular steel tubes under combined compressive axial load and bending decreases with the increase of slenderness ratio and eccentricity,and is less affected by the diameter-thickness ratio.(3)Compare the numerical simulation results of the 396 parameter analysis examples with the design formulas of the overall stable bearing capacity of the axial compression and bias components in multinational design codes.It is recommended that the axial compression components of high-strength hot-rolled seamless circular steel tubes can be directly based on China's "Standard for design of steel structures" GB50017-2017 design regulations are checked,but the members under combined compressive axial load and bending of the overall stability check formula should be introduced into the correction factor to consider the effect of slenderness ratio and eccentricity.