Q420高强角钢子结构的力学性能试验研究

Experimental Study on Mechanical Behavior of Q420 High-Strength Angle Steel in Substructure

为研究哈密北部750kV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 Q420high-strength angle steel of 750 kV transmission tower in north Hami,the destructive static tests of Q420high-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 Q420high-strength angle steel were analyzed deeply.The results show：The ultimate bearing capacity of the substructure of the Q420high-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 Q420high-strength angle steel,which mainly occurs in the bottom of the substructure.