Q420高强角钢子结构的力学性能试验研究

摘要

为研究哈密北部750 kV输电塔架实际工程中的 Q420高强角钢的力学性能，对三种不同主杆节间长度的 Q420高强角钢输电塔腿试件进行了破坏性静力试验。在试验研究的基础上，对 Q420高强角钢的材料性能、极限承载力、破坏模式和应变幅值等进行了分析。结果表明：子结构中 Q420高强角钢的极限承载力远大于相同长细比单根角钢的承载力，且随着主杆节间长度的增大，其极限承载力呈减小趋势；子结构的破坏模式主要为 Q420高强角钢主杆的扭转屈曲，且变形主要发生在子结构的底部。%To study the mechanical behavior of Q420 high?strength angle steel of 750 kV transmission tower in north Hami,the destructive static tests of Q420 high?strength angle steel with three different main stem internodal length of transmission tower legs were conducted.Based on the experimental research,the material property,ultimate bearing capacity,failure modes and deformation amplitude of Q420 high-strength angle steel were analyzed deeply.The results show:The ultimate bearing capacity of the substructure of the Q420 high?strength angle steel is greater than the bearing capacity of single angle steel with same slenderness ratio,and with the increase of the main stem internodal length,the ultimate bearing capacity decreases;The failure modes of the substructure is mainly torsional buckling of the Q420 high?strength angle steel,which mainly occurs in the bottom of the substructure.