Q420等边角钢输电塔腿轴压试验研究及数值分析

摘要

In order to fully investigate into the mechanical behavior of Q420 high strength angle steel in the actual transmission tower,the compression test research is conducted on Q420 high strength angle steel as the substructure of legs for transmission tower.On the basis of the test results,the influence of the initial defects of the test specimen during the process and installation to Q420 high strength angle steel is taken into consideration,and the finite element numerical a-nalysis research is made of the substructure of legs for transmission tower.Such indexes as the stress distribution,deformation behaviors,failure mode and limit bearing capacity of Q420 equal angle steel in tower legs structure are systematically discussed.The research results indicate that numerical analysis results are found to be in good coincidence with test results.Particularly in bearing capacity,there is only 5%~10% of differences between the both.The high strength an-gle steels in substructure appear to be bending torsional buckling,and their bearing capacity is much higher than the limit values set in《Code for design of steel structures》(GB50017-2003). Accordingly,it is suggested that when transmission tower is designed,the overall effect upon the bearing capacity of Q420 high strength angle steel be taken into account.%为充分认识 Q420高强角钢在实际输电塔架中的受力性能，对使用 Q420高强角钢作为输电塔架塔腿的子结构进行了抗压试验研究。本文基于试验研究成果，考虑了试件加工及试件安装的初始缺陷对 Q420高强角钢的影响，对塔腿子结构进行了有限元数值分析研究，系统探讨了塔腿子结构中 Q420等边角钢的应力分布、变形特征与破坏模式、极限承载力等指标。研究结果表明：数值分析结果与试验结果具有很好的吻合程度，尤其在承载力方面，两者相差仅5％～10％；子结构中的高强角钢受压后均呈现出弯扭的失稳形式，且承载力远高于 GB50017-2003《钢结构设计规范》限值，建议输电塔设计时考虑整体效应对 Q420高强角钢承载力的影响。