Fatigue failure analysis of platform screen doors under subway aerodynamic loads using finite element modeling

Abstract

This study presents an investigation into the fatigue failure mechanisms of platform screen doors (PSDs) subjected to aerodynamic loads generated by high-speed subway trains. A comprehensive finite element model is developed, integrating with fast Fourier transform (FFT) techniques to isolate and evaluate pulsating wind frequencies that impact the structural behavior of PSDs. The extracted wind frequencies and transient vibration responses are analyzed to determine their effects on structural stability. A load-stress transmission model is introduced to convert aerodynamic load data into structural stress time histories, enabling detailed fatigue assessments. Additionally, a stress distribution model is constructed to capture variations in maximum stress under different train speeds and distances from the track centerline. The Brittle Cracking model is applied to assess potential damage to glass components, revealing that the wind load frequency remains significantly lower than the structure’s natural frequency, thereby preventing resonance-induced failure. To evaluate long-term performance, fatigue damage assessments of critical components (such as the bottom support, door frame, and bottom plate) are conducted using both Miner’s cumulative damage criterion and a nonlinear damage model based on fatigue driving force energy. The analysis demonstrates that the maximum equivalent damage values for these components are within safe limits over a 30-year design life, with values of 0.59, 0.06, and 0.27 for the linear model, and 0.65, 0.07, and 0.29 for the nonlinear model. The study concludes by proposing an optimized design for the bottom support structure, reducing structural damage by about 45%. This research provides innovative insights into improving the durability, safety, and performance of PSDs under dynamic aerodynamic loading, contributing both to theoretical advancements and practical applications in urban transit infrastructure.