【摘要】 为研究下击暴流作用下输电塔结构的倒塌机理,在考虑输电塔结构的塔身主杆和腹杆的杆件失稳特征差异基础上,建立塔身主杆失稳的弯矩-轴力-轴向刚度关系曲面,并重现下击暴流强风作用下输电塔主杆受压弹塑性失稳破坏的全过程,得到输电塔在下击暴流强风荷载作用下倒塌时塔身斜腹杆和主杆失稳破坏的顺序。结果表明,在下击暴流强风作用下,输电塔在中上部和中下部的交接部位有大量塔身斜腹杆和少量塔身主杆相继发生失稳破坏,进而引起输电线塔结构整体倒塌。更多还原

【Abstract】 In order to research the collapse mechanism of transmission tower under downburst strong wind,the moment-axial force-axial stiffness relationship of main chord members during buckling was proposed with considering the different buckling characteristics of chord and web members. Then,an elastic-plastic buckling analysis of transmission tower under downburst strong wind was accomplished. The whole elastic-plastic buckling collapse process of transmission tower was studied,and buckling damage order of chord and web members was obtained. The results indicate that the key part inducing the transmission tower collapse is the joint region between the upper and lower parts,where buckling damage to many web members and several main chord members has been caused successively by the action of downburst strong wind.更多还原