Probabilistic Analysis of Structural Reliability of Leaning Poles in Power Distribution Infrastructure Systems under Extreme Wind Loads

摘要

Leaning utility poles are often overlooked in maintenance. Once a utility pole leans to one side, it generates a non-uniform stress distribution on the ground, which leads to decreased structural stability. Therefore, even if leaning poles have not fallen for the present, they pose more potential probability of failure than straight poles. Despite the significance, the extent to which leaning poles are vulnerable to wind loads has not been folly explored. This paper aims to evaluate the probability of failure of leaning poles under extreme wind loads. For analyzing the structural reliability, two failure modes are considered: flexural failure due to wind load and overturning failure by leaning. Based on the two failure modes, fragility curves for utility poles with respect to the angle of the leaning are developed. The developed fragility curves were used to identify potentially vulnerable poles in power distribution infrastructure networks in Houston, TX, when potential extreme wind events occur. The proposed method will benefit practitioners by facilitating effective risk-informed decision-making to prioritize maintenance tasks over numerous leaning poles in power distribution infrastructure systems before hurricane seasons, which helps enhance the community resilience to cascading blackout.