Simple derailing failure in electrical transmission towers and mitigating solutions structures

This paper introduces a novel approach called “derailing” aimed at reducing the cost and time associated with assessing structural damages of electrical transmission towers (ETT). Traditional monitoring methods for ETT structures involve on-site visits, extensive modeling, and full-scale testing, which can be cumbersome and expensive due to the large number of transmission line towers. The proposed approach focuses on identifying the primary and secondary coordinates of critical nodes in transmission tower damages using drone photography data. To validate the critical nodes identified by the derailing approach, retrofitted and non-retrofitted towers were analyzed using the finite element method (FEM). The analysis of the derailing method revealed that critical nodes located in the lower segment of the tower, especially in the non-retrofitted tower, experienced a substantial 95.4% increase in drift due to support settlement, while retrofitted towers showed a significantly lower increase of 55.5%. The findings from the FEM and observed failures in existing towers corroborated the results obtained from the derailing method, highlighting the vulnerability of the lower segment of the tower, both with and without settlement. Furthermore, it was observed that the addition of an extra diaphragm in this section of the tower structure improved its performance, making it comparable to that of the non-retrofitted tower without settlement. Consequently, the derailing approach for predicting failures and effectively monitoring the structural integrity of ETT and the implementation of diaphragm in the tower lower segment for controlling the nodes derailing might be employed for further analyses, such as the reliability.