ZS型老旧杆塔自动化建模及承载特性分析

Automatic numerical simulation of ZS-type transmission tower and its bearing capability analysis

为探求不利工况下ZS型老旧杆塔的力学响应,解释其在大风作用下倒塌的原因,以110 kV ZS型架空输电塔为例,通过编制自动化建模程序建立结构的有限元模型,分析不同风载荷工况下电塔的静力承载性能,并基于振型叠加理论分析电塔的动力承载特性。结果表明:ZS型输电塔抗扭性能差且塔身中部为薄弱部分,由于承载力不足,在不利荷载作用下容易发生破坏从而导致整体的倒塌。基于电塔的承载力分析,提出相应的加固方案,数值模拟表明加固后主材的承载力比显著降低,验证了加固方案的有效性。

In order to investigate the mechanical response and interpret the key collapsing reason of old transmission towers under unfavorable conditions of strong winds,an automatic numerical simulation method has been developed with emphasis on the 110 kV ZS-type of overhead transmission towers.The static bearing capacity of components under different load conditions as well as dynamic characters of the structure were analyzed in this study based on the proposed simulation method and mode superposition theory.The results show that the middle section of the ZS-type transmission tower is the weakest section.Thus,the relatively weak middle section combined with insufficient anti-twist capacity of the tower is the main cause of its structural collapse.On this basis,structural reinforcement and performance improvement can be carried out,which were verified by the numerical model.