Failure Probability Analysis of Lattice Wind Turbine Towers Under Combined Wind and Earthquake Action

Abstract

With wind farms expanding into seismically active areas, wind turbines face the combined hazard of wind and earthquakes. Strong winds often accompany strong earthquakes, posing a significant threat to wind turbine safety. When subjected to multihazard loads, ignoring the correlation between loads could underestimate the risk to the structure. However, there is limited research on wind turbines under the combined effect of wind and earthquakes. In this paper, based on historical data considering the correlation between wind and earthquakes, a failure probability analysis method for wind turbine towers under the joint action of wind and earthquakes is presented. To accurately simulate the mechanical behavior of lattice-type wind turbine towers, the bolt slippage effect is taken into account. A finite element model of a lattice wind turbine tower is established, and the failure probability of the tower under the joint action of wind and earthquakes is calculated. The study also analyzes the influence of the bolt slippage effect and load correlation on the reliability of lattice-type wind turbine towers. The results indicate that ignoring load correlation can underestimate the failure probability of the structure, thus decreasing its safety. Similarly, ignoring the bolt slippage effect can also underestimate the failure probability of the structure and seriously threaten the safety of wind turbines.