大跨越输电塔的地震响应研究

以500kV榕江大跨越输电线路工程为背景.选取3条地震波作为地震输入,用时程分析方法研究输电塔一线体系地震响应与输入地震波的关系。通过研究得出:横线向与顺线向地震对单塔模型的作用效果基本相同;横线向地震作用下。塔线模型中塔顶的顺线向响应是由输电线仅受初始激励下的自由摆动而产生的,与地震波的类型与峰值无关。输电线对输电塔的横线向振动并无影响。仅仅降低了其在横线向的响应峰值;顺线向地震作用下,塔顶的顺线向位移响应主要与输电线的振动有关,但同时也与输入地震波的类型与峰值相关;输电塔的地震响应以顺线向为主。  

Study on Seismic Responses of Large Crossing Span Transmission Towers

Using 500 kV Rongjiang River large crossing line as an example,and choosing 3 seismic waves as input,time-history analysis is used to study relationship between input waves and tower-conductor system responses.Results show that lateral and longitudinal earthquake has almost same effect on single tower model;under lateral wave,tower top longitudinal response in tower-conductor model is caused by conductor free oscillation under initial excitation only,and has nothing to do with wave type and its peak value;conductor has no influence on tower lateral vibration,but only reduces the peak value of its lateral response;under longitudinal wave,tower top longitudinal displacement is mainly affected by conductor vibration,in the mean time,it is also affected by wave type and peak value;so tower seismic response is mainly longitudinal.