The development of a diagnostic approach that predicts failure risk of flexible road pavements

Understanding the exact cause of road pavement failure can be complicated, given the number of interacting factors and failure mechanisms. To further complicate the task, limited funding puts pressure on asset managers to make the right decisions for preserving the asset. Maintenance is often applied to address surface defects as opposed to the underlying cause of failure, often because the underlying cause of failure is unknown. To address this, a comprehensive understanding of pavement failure has been developed. This paper documents the development of a risk index that uses a diagnostic approach, based on a fundamental understanding of pavement failure, to identify the cause of road pavement failure. The concept behind this index is discussed with particular attention to incorporating engineering knowledge into pavement performance modelling and asset management. In addition, the results from a case study of New Zealand low-volume roads are presented, which demonstrate the ideas of this research in practice.