以徐连输电工程沉陷区上输电线路为背景，分析了输电线路经过地区的煤炭开采状况。以输电铁塔内典型杆件失稳破坏时的支座位移作为判断塔架是否安全的标准，得到了沉陷区输电杆塔抵抗地表变形的能力，并将其作为铁塔变形的允许值；根据沉陷区地表变形预计结果，对位于沉陷区的输电线路的安全性进行了评估。分析表明，老采空区地表变形对输电铁塔安全性的影响很小，输电铁塔是安全的；煤层全部采完后，地表变形对典型输电铁塔安全性有一定影响，必须采用复合防护板基础，铁塔抵抗地表水平变形的能力才能够满足要求。但是，对输电线路倾斜值和地表沉降过大的问题，需采用相应的技术措施。目前，位于沉陷区的输电线路和杆塔未发现异常情况，运行状况良好。

On the background of Xulian Transmission lines in the mining subsidence region, the coal mining status under these subsidence areas was analyzed. The support displacement of the transmission towers because of typical bars’ stability failure was set to be the safety criterion. And the ultimate deformation of the tower attained through analysis was considered as the deformation limit of the tower. According to the expected results of the surface deformation in subsidence area, the reliabil-ity of the transmission lines across the subsidence area was assessed. Analysis shows that the surface deformation of the old mined-out area has little impact on the safety of the transmission tower. However, when coal mining is end, it is necessary to adopt composite foundation, that's because the composite foundation's anti-deformation capability is enough to withstand the impact of the surface deformation. As to the large inclination and the surface subsidence, appropriate technical measures are needed. Currently transmission lines and towers in the subsidence areas were found run-ning in good condition without abnormalities.