Q460输电钢管杆长圆形截面宽厚比限值研究
Research on Limit Value of Width to Thickness Ratio of Long Circular ？？Section in Q460 Steel Transmission Pole

为研究Q460输电钢管杆长圆形截面长直边的宽厚比限值，防止管壁局部失稳先于钢管杆强度破坏，首先比较不同规范对方形和箱型截面宽厚比限值的规定，进而确定试验试件的宽厚比参数，并进行了3组不同宽厚比试件的压弯试验；然后利用有限元软件进行非线性数值分析，结合试验结果对试件破坏形态进行考察；最后将试验、有限元分析与按规范计算的承载力进行比较，提出了合理的长圆形截面长直边宽厚比限值。研究结果表明：长圆形截面长直边宽厚比限值参照美国杆塔规范ASCE/SEI 48？？05（十二边形）取为29.5，超限部分则按规范中相应公式对受压翼缘截面强度进行折减；若需设置内肋，长直边的宽厚比限值依据美国杆塔规范ASCE/SEI 48？？05（四边形）取为31.5是可靠的。
In order to analyze the limit value of width to thickness ratio of long straight edge in the Q460 steel transmission pole section and prevent local buckling happening before strength failure, firstly, different codes about width to thickness ratios of square section and box section were compared. According to the ratios, the limit values of width to thickness ratio of experiment specimen were designed, and three groups of compression？？bending experiments were carried out. Combined with experiments, the failure modes were analyzed, and the nonlinear numerical analysis was carried out by finite element software. Through the comparisons of bearing capacities of finite element analysis, experiment and American code, a rational limit value of width to thickness ratio of long circular section was presented. The study results show that referring to American design of steel transmission pole structures ASCE/SEI 48？？05(dodecagon), the thickness ratio of long straight edge in long circular section can choose 29.5 and for the transfinite part, compression flange strength shall be taken a reduction according to relevant formulas in code. If ribbed plates are needed, it is reliable to choose 31.5 as the thickness ratio of long straight edge on the basis of ASCE/SEI 48？？05(quadrilateral)