Theoretical And Experimental Study On Integral Stability Of High Strength (Q460) Angle Bars To Axial Compression

High strength(Q460) steel-angle members have the high load-carrying capacity, which alleviate complicated joint structure and make installation unheavy.This kind of steel-angle reduces the consumption of resource and investment.With the continous development of electric transmission line of high voltage,the high strength grade steel-angle is widely used.Recent years,many studies on the property of this kind of angle have been carried out in China,such as Q390 and Q420.However,the design of Q460 structural steel is less.For the demand of design,theoretical analysis,testing and FEM calculating are included in this paper to study the buckling capacity.Equilateral single-angle steel is uniaxial symmetric section.Except bending instability about the asymmetric axis,it is bending and torsion instability on the other axis.To verify the rationality of the theoretical deduction,axial compression test and related material test of four different sections with each section having varied slenderness have been used.The stability behavior of axially compressed hign strength (Q460) steel-angle is studied,and the formula of Code for Design of Steel Structure GB50017-2003 and Design of Latticed Steel Transmission Structures ASCE10-1997 are also verified.Then the ANSYS-finite element analysis software is used to study the stability of hign strength(Q460) steel-angle,in which the factors such as residual stresses and geometric imperfections are considered.After comparing and analyzing, the buckling mode can be determined by the different slenderness ratio.Whenλ≥60, it is bending buckling,and it is local buckling whenλ＜60.Ultimate bearing capacity can improve 15%to 30%comparing with Q235 and Q345.The calculation of ultimate bearing capacity for code GB50017-2003 is much more conservative,which is not applicable for project.But the code for ASCE10-1997 is closer to the carrying capacity,which as a basis for the design.Finite element analysis accurately simulates the buckling mode of axially compressed bar and reflects the ture carrying capacity,...