Corrugation Control in Unsealed Roads: Mechanisms and Sustainable Solutions

This project tackles the long-standing problem of corrugation (washboarding) in unsealed roads, a major issue affecting over 500,000 km of road infrastructure in Australia. Corrugation reduces safety, increases vehicle operating costs by up to 50%, and drives substantial maintenance expenses for local governments and regional communities.

The research combines geotechnical engineering, unsaturated soil mechanics, and vehicle–road interaction modelling to uncover the fundamental mechanisms driving corrugation formation. It investigates how climatic effects, particularly drying and moisture fluctuations, interact with material properties and traffic-induced stresses to trigger surface instability.

The project introduces several innovations, including a first-of-its-kind laboratory corrugation test, advanced numerical modelling using Smoothed Particle Hydrodynamics (SPH), and AI-assisted predictive tools. These approaches enable detailed analysis of how corrugations initiate, evolve, and stabilise under real-world conditions.

Building on these insights, the project develops sustainable engineering solutions, including optimised granular materials, recycled material blends, and stabilising additives designed to resist corrugation. It also produces practical tools and guidelines for road authorities, allowing proactive maintenance and improved material selection tailored to local climates and traffic conditions.
The outcomes will reduce maintenance frequency, lower environmental impacts such as dust emissions, and improve safety and accessibility for remote communities. By shifting from reactive maintenance to predictive, performance-based design, this project delivers both scientific advancement and tangible economic and societal benefits.

Funding Sources to be Acknowledged:
Australian Research Council Discovery Program

Project Team and Collaborators:
Prof Jayantha Kodikara (Monash University); Dr Liuxin Chen; Erol Tutumluer (UIUC, USA)