Failure Analysis of Transmission Tower under the Effect of Ice-Covered Power Transmission Line

Ice storm is a kind of extreme weather conditions that can cause great losses to electric power system. The payments of power transmission towers account for 40 percent of total investment. For this, research on ultimate load and failure mechanism of transmission tower is very necessary. The property of ice coating is summarized in this paper. Also, the lateral load, the longitudinal load, and the vertical load of transmission tower under the effect of ice coating are discussed in detail. Taking a tangent tower as an example, finite element model is built with the consideration of beam element orientations. On these bases, the calculation of ultimate load capacity of the transmission tower is carried out in this paper. The results show that the mechanic behavior of transmission tower is similar to steel member, which can be approximately divided into three different stages: elastic stage, yield stage and strengthen stage.