Quantitative Assessment of Factors Influencing Masonry Arch Bridge Performance

Abstract

The performance and longevity of masonry arch bridges depend on several interrelated factors, with ageing, design, monitoring, and environmental conditions being the most significant. Ageing alone contributes to nearly 40% of structural deterioration, as long-term fatigue leads to cracks, misalignment, and loss of structural capacity. Design and construction issues account for approximately 25% of observed failures, often due to poor load distribution or inadequate arch geometry. Environmental impacts, including moisture, chemical weathering, and freeze–thaw cycles, represent around 20% of degradation, weakening both the masonry materials and bonding agents. Traffic loads further add strain, increasing stress levels by up to 15% across the bridge’s lifespan, especially under heavy vehicles. Despite these risks, monitoring and inspection practices remain insufficient in many cases. Traditional inspections may miss hidden defects, while advanced tools such as laser scanning, ultrasound, and drone-based monitoring can detect over 90% of internal or concealed damage compared to conventional methods. By applying quantitative assessment methods to evaluate these factors, engineers can prioritise critical vulnerabilities, design effective maintenance strategies, and enhance overall resilience. This systematic evaluation not only supports evidence-based preservation but also ensures that limited resources are directed toward the most impactful interventions, extending the service life of masonry arch bridges and safeguarding their structural and cultural value for future generations