Bridges

Stirling Bridge is a pivotal transport artery in Perth, linking Fremantle port to the broader Western Australia region and facilitating the majority of container trade. Constructed in 1974, its unconventional span arrangement — with a south abutment span of under 23 m and a maximum span of 80 m — required the use of Macalloy bars to stabilise the structure. This unique design has driven a comprehensive investigation into fatigue behaviour, a critical element of the bridge’s structural health monitoring regime.

Recognising that the initial fatigue assessment, based on AS5100 standards, was overly conservative, a digital twin approach was implemented for long-term monitoring. This advanced framework integrates an array of sensors with state-of-the-art computer vision algorithms to capture precise strain and displacement data. By employing both the Palmgren-Miner method and conventional rainflow counting techniques, the digital twin enables a refined analysis of fatigue, accurately accounting for the contributions of various vehicle classes.

The continuous data acquisition from strategically mounted cameras and sensors not only delivers a realistic estimate of the bridge’s remaining design life but also informs more effective maintenance strategies and safety protocols. Integrating computer vision with sensor data within a digital twin model exemplifies a modern approach to structural health monitoring, offering significant insights into fatigue dynamics. The outcomes of this study hold substantial practical implications for the optimisation of infrastructure management, making them highly relevant to both industry professionals and academic researchers.